before send to remote

env/lib/python3.8/site-packages/pip/_internal/utils/appdirs.py

@@ -0,0 +1,44 @@
+"""
+This code wraps the vendored appdirs module to so the return values are
+compatible for the current pip code base.
+
+The intention is to rewrite current usages gradually, keeping the tests pass,
+and eventually drop this after all usages are changed.
+"""
+
+from __future__ import absolute_import
+
+import os
+
+from pip._vendor import appdirs as _appdirs
+
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import List
+
+
+def user_cache_dir(appname):
+    # type: (str) -> str
+    return _appdirs.user_cache_dir(appname, appauthor=False)
+
+
+def user_config_dir(appname, roaming=True):
+    # type: (str, bool) -> str
+    return _appdirs.user_config_dir(appname, appauthor=False, roaming=roaming)
+
+
+def user_data_dir(appname, roaming=False):
+    # type: (str, bool) -> str
+    return _appdirs.user_data_dir(appname, appauthor=False, roaming=roaming)
+
+
+# for the discussion regarding site_config_dir locations
+# see <https://github.com/pypa/pip/issues/1733>
+def site_config_dirs(appname):
+    # type: (str) -> List[str]
+    dirval = _appdirs.site_config_dir(appname, appauthor=False, multipath=True)
+    if _appdirs.system not in ["win32", "darwin"]:
+        # always look in /etc directly as well
+        return dirval.split(os.pathsep) + ['/etc']
+    return [dirval]

env/lib/python3.8/site-packages/pip/_internal/utils/compat.py

@@ -0,0 +1,269 @@
+"""Stuff that differs in different Python versions and platform
+distributions."""
+
+# The following comment should be removed at some point in the future.
+# mypy: disallow-untyped-defs=False
+
+from __future__ import absolute_import, division
+
+import codecs
+import locale
+import logging
+import os
+import shutil
+import sys
+
+from pip._vendor.six import PY2, text_type
+
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Optional, Text, Tuple, Union
+
+try:
+    import ipaddress
+except ImportError:
+    try:
+        from pip._vendor import ipaddress  # type: ignore
+    except ImportError:
+        import ipaddr as ipaddress  # type: ignore
+        ipaddress.ip_address = ipaddress.IPAddress  # type: ignore
+        ipaddress.ip_network = ipaddress.IPNetwork  # type: ignore
+
+
+__all__ = [
+    "ipaddress", "uses_pycache", "console_to_str",
+    "get_path_uid", "stdlib_pkgs", "WINDOWS", "samefile", "get_terminal_size",
+]
+
+
+logger = logging.getLogger(__name__)
+
+if PY2:
+    import imp
+
+    try:
+        cache_from_source = imp.cache_from_source  # type: ignore
+    except AttributeError:
+        # does not use __pycache__
+        cache_from_source = None
+
+    uses_pycache = cache_from_source is not None
+else:
+    uses_pycache = True
+    from importlib.util import cache_from_source
+
+
+if PY2:
+    # In Python 2.7, backslashreplace exists
+    # but does not support use for decoding.
+    # We implement our own replace handler for this
+    # situation, so that we can consistently use
+    # backslash replacement for all versions.
+    def backslashreplace_decode_fn(err):
+        raw_bytes = (err.object[i] for i in range(err.start, err.end))
+        # Python 2 gave us characters - convert to numeric bytes
+        raw_bytes = (ord(b) for b in raw_bytes)
+        return u"".join(u"\\x%x" % c for c in raw_bytes), err.end
+    codecs.register_error(
+        "backslashreplace_decode",
+        backslashreplace_decode_fn,
+    )
+    backslashreplace_decode = "backslashreplace_decode"
+else:
+    backslashreplace_decode = "backslashreplace"
+
+
+def has_tls():
+    # type: () -> bool
+    try:
+        import _ssl  # noqa: F401  # ignore unused
+        return True
+    except ImportError:
+        pass
+
+    from pip._vendor.urllib3.util import IS_PYOPENSSL
+    return IS_PYOPENSSL
+
+
+def str_to_display(data, desc=None):
+    # type: (Union[bytes, Text], Optional[str]) -> Text
+    """
+    For display or logging purposes, convert a bytes object (or text) to
+    text (e.g. unicode in Python 2) safe for output.
+
+    :param desc: An optional phrase describing the input data, for use in
+        the log message if a warning is logged. Defaults to "Bytes object".
+
+    This function should never error out and so can take a best effort
+    approach. It is okay to be lossy if needed since the return value is
+    just for display.
+
+    We assume the data is in the locale preferred encoding. If it won't
+    decode properly, we warn the user but decode as best we can.
+
+    We also ensure that the output can be safely written to standard output
+    without encoding errors.
+    """
+    if isinstance(data, text_type):
+        return data
+
+    # Otherwise, data is a bytes object (str in Python 2).
+    # First, get the encoding we assume. This is the preferred
+    # encoding for the locale, unless that is not found, or
+    # it is ASCII, in which case assume UTF-8
+    encoding = locale.getpreferredencoding()
+    if (not encoding) or codecs.lookup(encoding).name == "ascii":
+        encoding = "utf-8"
+
+    # Now try to decode the data - if we fail, warn the user and
+    # decode with replacement.
+    try:
+        decoded_data = data.decode(encoding)
+    except UnicodeDecodeError:
+        if desc is None:
+            desc = 'Bytes object'
+        msg_format = '{} does not appear to be encoded as %s'.format(desc)
+        logger.warning(msg_format, encoding)
+        decoded_data = data.decode(encoding, errors=backslashreplace_decode)
+
+    # Make sure we can print the output, by encoding it to the output
+    # encoding with replacement of unencodable characters, and then
+    # decoding again.
+    # We use stderr's encoding because it's less likely to be
+    # redirected and if we don't find an encoding we skip this
+    # step (on the assumption that output is wrapped by something
+    # that won't fail).
+    # The double getattr is to deal with the possibility that we're
+    # being called in a situation where sys.__stderr__ doesn't exist,
+    # or doesn't have an encoding attribute. Neither of these cases
+    # should occur in normal pip use, but there's no harm in checking
+    # in case people use pip in (unsupported) unusual situations.
+    output_encoding = getattr(getattr(sys, "__stderr__", None),
+                              "encoding", None)
+
+    if output_encoding:
+        output_encoded = decoded_data.encode(
+            output_encoding,
+            errors="backslashreplace"
+        )
+        decoded_data = output_encoded.decode(output_encoding)
+
+    return decoded_data
+
+
+def console_to_str(data):
+    # type: (bytes) -> Text
+    """Return a string, safe for output, of subprocess output.
+    """
+    return str_to_display(data, desc='Subprocess output')
+
+
+def get_path_uid(path):
+    # type: (str) -> int
+    """
+    Return path's uid.
+
+    Does not follow symlinks:
+        https://github.com/pypa/pip/pull/935#discussion_r5307003
+
+    Placed this function in compat due to differences on AIX and
+    Jython, that should eventually go away.
+
+    :raises OSError: When path is a symlink or can't be read.
+    """
+    if hasattr(os, 'O_NOFOLLOW'):
+        fd = os.open(path, os.O_RDONLY | os.O_NOFOLLOW)
+        file_uid = os.fstat(fd).st_uid
+        os.close(fd)
+    else:  # AIX and Jython
+        # WARNING: time of check vulnerability, but best we can do w/o NOFOLLOW
+        if not os.path.islink(path):
+            # older versions of Jython don't have `os.fstat`
+            file_uid = os.stat(path).st_uid
+        else:
+            # raise OSError for parity with os.O_NOFOLLOW above
+            raise OSError(
+                "%s is a symlink; Will not return uid for symlinks" % path
+            )
+    return file_uid
+
+
+def expanduser(path):
+    # type: (str) -> str
+    """
+    Expand ~ and ~user constructions.
+
+    Includes a workaround for https://bugs.python.org/issue14768
+    """
+    expanded = os.path.expanduser(path)
+    if path.startswith('~/') and expanded.startswith('//'):
+        expanded = expanded[1:]
+    return expanded
+
+
+# packages in the stdlib that may have installation metadata, but should not be
+# considered 'installed'.  this theoretically could be determined based on
+# dist.location (py27:`sysconfig.get_paths()['stdlib']`,
+# py26:sysconfig.get_config_vars('LIBDEST')), but fear platform variation may
+# make this ineffective, so hard-coding
+stdlib_pkgs = {"python", "wsgiref", "argparse"}
+
+
+# windows detection, covers cpython and ironpython
+WINDOWS = (sys.platform.startswith("win") or
+           (sys.platform == 'cli' and os.name == 'nt'))
+
+
+def samefile(file1, file2):
+    # type: (str, str) -> bool
+    """Provide an alternative for os.path.samefile on Windows/Python2"""
+    if hasattr(os.path, 'samefile'):
+        return os.path.samefile(file1, file2)
+    else:
+        path1 = os.path.normcase(os.path.abspath(file1))
+        path2 = os.path.normcase(os.path.abspath(file2))
+        return path1 == path2
+
+
+if hasattr(shutil, 'get_terminal_size'):
+    def get_terminal_size():
+        # type: () -> Tuple[int, int]
+        """
+        Returns a tuple (x, y) representing the width(x) and the height(y)
+        in characters of the terminal window.
+        """
+        return tuple(shutil.get_terminal_size())  # type: ignore
+else:
+    def get_terminal_size():
+        # type: () -> Tuple[int, int]
+        """
+        Returns a tuple (x, y) representing the width(x) and the height(y)
+        in characters of the terminal window.
+        """
+        def ioctl_GWINSZ(fd):
+            try:
+                import fcntl
+                import termios
+                import struct
+                cr = struct.unpack_from(
+                    'hh',
+                    fcntl.ioctl(fd, termios.TIOCGWINSZ, '12345678')
+                )
+            except Exception:
+                return None
+            if cr == (0, 0):
+                return None
+            return cr
+        cr = ioctl_GWINSZ(0) or ioctl_GWINSZ(1) or ioctl_GWINSZ(2)
+        if not cr:
+            if sys.platform != "win32":
+                try:
+                    fd = os.open(os.ctermid(), os.O_RDONLY)
+                    cr = ioctl_GWINSZ(fd)
+                    os.close(fd)
+                except Exception:
+                    pass
+        if not cr:
+            cr = (os.environ.get('LINES', 25), os.environ.get('COLUMNS', 80))
+        return int(cr[1]), int(cr[0])

env/lib/python3.8/site-packages/pip/_internal/utils/deprecation.py

@@ -0,0 +1,104 @@
+"""
+A module that implements tooling to enable easy warnings about deprecations.
+"""
+
+# The following comment should be removed at some point in the future.
+# mypy: disallow-untyped-defs=False
+
+from __future__ import absolute_import
+
+import logging
+import warnings
+
+from pip._vendor.packaging.version import parse
+
+from pip import __version__ as current_version
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Any, Optional
+
+
+DEPRECATION_MSG_PREFIX = "DEPRECATION: "
+
+
+class PipDeprecationWarning(Warning):
+    pass
+
+
+_original_showwarning = None  # type: Any
+
+
+# Warnings <-> Logging Integration
+def _showwarning(message, category, filename, lineno, file=None, line=None):
+    if file is not None:
+        if _original_showwarning is not None:
+            _original_showwarning(
+                message, category, filename, lineno, file, line,
+            )
+    elif issubclass(category, PipDeprecationWarning):
+        # We use a specially named logger which will handle all of the
+        # deprecation messages for pip.
+        logger = logging.getLogger("pip._internal.deprecations")
+        logger.warning(message)
+    else:
+        _original_showwarning(
+            message, category, filename, lineno, file, line,
+        )
+
+
+def install_warning_logger():
+    # type: () -> None
+    # Enable our Deprecation Warnings
+    warnings.simplefilter("default", PipDeprecationWarning, append=True)
+
+    global _original_showwarning
+
+    if _original_showwarning is None:
+        _original_showwarning = warnings.showwarning
+        warnings.showwarning = _showwarning
+
+
+def deprecated(reason, replacement, gone_in, issue=None):
+    # type: (str, Optional[str], Optional[str], Optional[int]) -> None
+    """Helper to deprecate existing functionality.
+
+    reason:
+        Textual reason shown to the user about why this functionality has
+        been deprecated.
+    replacement:
+        Textual suggestion shown to the user about what alternative
+        functionality they can use.
+    gone_in:
+        The version of pip does this functionality should get removed in.
+        Raises errors if pip's current version is greater than or equal to
+        this.
+    issue:
+        Issue number on the tracker that would serve as a useful place for
+        users to find related discussion and provide feedback.
+
+    Always pass replacement, gone_in and issue as keyword arguments for clarity
+    at the call site.
+    """
+
+    # Construct a nice message.
+    #   This is eagerly formatted as we want it to get logged as if someone
+    #   typed this entire message out.
+    sentences = [
+        (reason, DEPRECATION_MSG_PREFIX + "{}"),
+        (gone_in, "pip {} will remove support for this functionality."),
+        (replacement, "A possible replacement is {}."),
+        (issue, (
+            "You can find discussion regarding this at "
+            "https://github.com/pypa/pip/issues/{}."
+        )),
+    ]
+    message = " ".join(
+        template.format(val) for val, template in sentences if val is not None
+    )
+
+    # Raise as an error if it has to be removed.
+    if gone_in is not None and parse(current_version) >= parse(gone_in):
+        raise PipDeprecationWarning(message)
+
+    warnings.warn(message, category=PipDeprecationWarning, stacklevel=2)

env/lib/python3.8/site-packages/pip/_internal/utils/distutils_args.py

@@ -0,0 +1,48 @@
+from distutils.errors import DistutilsArgError
+from distutils.fancy_getopt import FancyGetopt
+
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Dict, List
+
+
+_options = [
+    ("exec-prefix=", None, ""),
+    ("home=", None, ""),
+    ("install-base=", None, ""),
+    ("install-data=", None, ""),
+    ("install-headers=", None, ""),
+    ("install-lib=", None, ""),
+    ("install-platlib=", None, ""),
+    ("install-purelib=", None, ""),
+    ("install-scripts=", None, ""),
+    ("prefix=", None, ""),
+    ("root=", None, ""),
+    ("user", None, ""),
+]
+
+
+# typeshed doesn't permit Tuple[str, None, str], see python/typeshed#3469.
+_distutils_getopt = FancyGetopt(_options)  # type: ignore
+
+
+def parse_distutils_args(args):
+    # type: (List[str]) -> Dict[str, str]
+    """Parse provided arguments, returning an object that has the
+    matched arguments.
+
+    Any unknown arguments are ignored.
+    """
+    result = {}
+    for arg in args:
+        try:
+            _, match = _distutils_getopt.getopt(args=[arg])
+        except DistutilsArgError:
+            # We don't care about any other options, which here may be
+            # considered unrecognized since our option list is not
+            # exhaustive.
+            pass
+        else:
+            result.update(match.__dict__)
+    return result

env/lib/python3.8/site-packages/pip/_internal/utils/encoding.py

@@ -0,0 +1,42 @@
+# The following comment should be removed at some point in the future.
+# mypy: strict-optional=False
+
+import codecs
+import locale
+import re
+import sys
+
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import List, Tuple, Text
+
+BOMS = [
+    (codecs.BOM_UTF8, 'utf-8'),
+    (codecs.BOM_UTF16, 'utf-16'),
+    (codecs.BOM_UTF16_BE, 'utf-16-be'),
+    (codecs.BOM_UTF16_LE, 'utf-16-le'),
+    (codecs.BOM_UTF32, 'utf-32'),
+    (codecs.BOM_UTF32_BE, 'utf-32-be'),
+    (codecs.BOM_UTF32_LE, 'utf-32-le'),
+]  # type: List[Tuple[bytes, Text]]
+
+ENCODING_RE = re.compile(br'coding[:=]\s*([-\w.]+)')
+
+
+def auto_decode(data):
+    # type: (bytes) -> Text
+    """Check a bytes string for a BOM to correctly detect the encoding
+
+    Fallback to locale.getpreferredencoding(False) like open() on Python3"""
+    for bom, encoding in BOMS:
+        if data.startswith(bom):
+            return data[len(bom):].decode(encoding)
+    # Lets check the first two lines as in PEP263
+    for line in data.split(b'\n')[:2]:
+        if line[0:1] == b'#' and ENCODING_RE.search(line):
+            encoding = ENCODING_RE.search(line).groups()[0].decode('ascii')
+            return data.decode(encoding)
+    return data.decode(
+        locale.getpreferredencoding(False) or sys.getdefaultencoding(),
+    )

env/lib/python3.8/site-packages/pip/_internal/utils/entrypoints.py

@@ -0,0 +1,31 @@
+import sys
+
+from pip._internal.cli.main import main
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Optional, List
+
+
+def _wrapper(args=None):
+    # type: (Optional[List[str]]) -> int
+    """Central wrapper for all old entrypoints.
+
+    Historically pip has had several entrypoints defined. Because of issues
+    arising from PATH, sys.path, multiple Pythons, their interactions, and most
+    of them having a pip installed, users suffer every time an entrypoint gets
+    moved.
+
+    To alleviate this pain, and provide a mechanism for warning users and
+    directing them to an appropriate place for help, we now define all of
+    our old entrypoints as wrappers for the current one.
+    """
+    sys.stderr.write(
+        "WARNING: pip is being invoked by an old script wrapper. This will "
+        "fail in a future version of pip.\n"
+        "Please see https://github.com/pypa/pip/issues/5599 for advice on "
+        "fixing the underlying issue.\n"
+        "To avoid this problem you can invoke Python with '-m pip' instead of "
+        "running pip directly.\n"
+    )
+    return main(args)

env/lib/python3.8/site-packages/pip/_internal/utils/filesystem.py

@@ -0,0 +1,171 @@
+import errno
+import os
+import os.path
+import random
+import shutil
+import stat
+import sys
+from contextlib import contextmanager
+from tempfile import NamedTemporaryFile
+
+# NOTE: retrying is not annotated in typeshed as on 2017-07-17, which is
+#       why we ignore the type on this import.
+from pip._vendor.retrying import retry  # type: ignore
+from pip._vendor.six import PY2
+
+from pip._internal.utils.compat import get_path_uid
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING, cast
+
+if MYPY_CHECK_RUNNING:
+    from typing import BinaryIO, Iterator
+
+    class NamedTemporaryFileResult(BinaryIO):
+        @property
+        def file(self):
+            # type: () -> BinaryIO
+            pass
+
+
+def check_path_owner(path):
+    # type: (str) -> bool
+    # If we don't have a way to check the effective uid of this process, then
+    # we'll just assume that we own the directory.
+    if sys.platform == "win32" or not hasattr(os, "geteuid"):
+        return True
+
+    assert os.path.isabs(path)
+
+    previous = None
+    while path != previous:
+        if os.path.lexists(path):
+            # Check if path is writable by current user.
+            if os.geteuid() == 0:
+                # Special handling for root user in order to handle properly
+                # cases where users use sudo without -H flag.
+                try:
+                    path_uid = get_path_uid(path)
+                except OSError:
+                    return False
+                return path_uid == 0
+            else:
+                return os.access(path, os.W_OK)
+        else:
+            previous, path = path, os.path.dirname(path)
+    return False  # assume we don't own the path
+
+
+def copy2_fixed(src, dest):
+    # type: (str, str) -> None
+    """Wrap shutil.copy2() but map errors copying socket files to
+    SpecialFileError as expected.
+
+    See also https://bugs.python.org/issue37700.
+    """
+    try:
+        shutil.copy2(src, dest)
+    except (OSError, IOError):
+        for f in [src, dest]:
+            try:
+                is_socket_file = is_socket(f)
+            except OSError:
+                # An error has already occurred. Another error here is not
+                # a problem and we can ignore it.
+                pass
+            else:
+                if is_socket_file:
+                    raise shutil.SpecialFileError("`%s` is a socket" % f)
+
+        raise
+
+
+def is_socket(path):
+    # type: (str) -> bool
+    return stat.S_ISSOCK(os.lstat(path).st_mode)
+
+
+@contextmanager
+def adjacent_tmp_file(path):
+    # type: (str) -> Iterator[NamedTemporaryFileResult]
+    """Given a path to a file, open a temp file next to it securely and ensure
+    it is written to disk after the context reaches its end.
+    """
+    with NamedTemporaryFile(
+        delete=False,
+        dir=os.path.dirname(path),
+        prefix=os.path.basename(path),
+        suffix='.tmp',
+    ) as f:
+        result = cast('NamedTemporaryFileResult', f)
+        try:
+            yield result
+        finally:
+            result.file.flush()
+            os.fsync(result.file.fileno())
+
+
+_replace_retry = retry(stop_max_delay=1000, wait_fixed=250)
+
+if PY2:
+    @_replace_retry
+    def replace(src, dest):
+        # type: (str, str) -> None
+        try:
+            os.rename(src, dest)
+        except OSError:
+            os.remove(dest)
+            os.rename(src, dest)
+
+else:
+    replace = _replace_retry(os.replace)
+
+
+# test_writable_dir and _test_writable_dir_win are copied from Flit,
+# with the author's agreement to also place them under pip's license.
+def test_writable_dir(path):
+    # type: (str) -> bool
+    """Check if a directory is writable.
+
+    Uses os.access() on POSIX, tries creating files on Windows.
+    """
+    # If the directory doesn't exist, find the closest parent that does.
+    while not os.path.isdir(path):
+        parent = os.path.dirname(path)
+        if parent == path:
+            break  # Should never get here, but infinite loops are bad
+        path = parent
+
+    if os.name == 'posix':
+        return os.access(path, os.W_OK)
+
+    return _test_writable_dir_win(path)
+
+
+def _test_writable_dir_win(path):
+    # type: (str) -> bool
+    # os.access doesn't work on Windows: http://bugs.python.org/issue2528
+    # and we can't use tempfile: http://bugs.python.org/issue22107
+    basename = 'accesstest_deleteme_fishfingers_custard_'
+    alphabet = 'abcdefghijklmnopqrstuvwxyz0123456789'
+    for i in range(10):
+        name = basename + ''.join(random.choice(alphabet) for _ in range(6))
+        file = os.path.join(path, name)
+        try:
+            fd = os.open(file, os.O_RDWR | os.O_CREAT | os.O_EXCL)
+        except OSError as e:
+            if e.errno == errno.EEXIST:
+                continue
+            if e.errno == errno.EPERM:
+                # This could be because there's a directory with the same name.
+                # But it's highly unlikely there's a directory called that,
+                # so we'll assume it's because the parent dir is not writable.
+                return False
+            raise
+        else:
+            os.close(fd)
+            os.unlink(file)
+            return True
+
+    # This should never be reached
+    raise EnvironmentError(
+        'Unexpected condition testing for writable directory'
+    )

env/lib/python3.8/site-packages/pip/_internal/utils/filetypes.py

@@ -0,0 +1,16 @@
+"""Filetype information.
+"""
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Tuple
+
+WHEEL_EXTENSION = '.whl'
+BZ2_EXTENSIONS = ('.tar.bz2', '.tbz')  # type: Tuple[str, ...]
+XZ_EXTENSIONS = ('.tar.xz', '.txz', '.tlz',
+                 '.tar.lz', '.tar.lzma')  # type: Tuple[str, ...]
+ZIP_EXTENSIONS = ('.zip', WHEEL_EXTENSION)  # type: Tuple[str, ...]
+TAR_EXTENSIONS = ('.tar.gz', '.tgz', '.tar')  # type: Tuple[str, ...]
+ARCHIVE_EXTENSIONS = (
+    ZIP_EXTENSIONS + BZ2_EXTENSIONS + TAR_EXTENSIONS + XZ_EXTENSIONS
+)

env/lib/python3.8/site-packages/pip/_internal/utils/glibc.py

@@ -0,0 +1,98 @@
+# The following comment should be removed at some point in the future.
+# mypy: strict-optional=False
+
+from __future__ import absolute_import
+
+import os
+import sys
+
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Optional, Tuple
+
+
+def glibc_version_string():
+    # type: () -> Optional[str]
+    "Returns glibc version string, or None if not using glibc."
+    return glibc_version_string_confstr() or glibc_version_string_ctypes()
+
+
+def glibc_version_string_confstr():
+    # type: () -> Optional[str]
+    "Primary implementation of glibc_version_string using os.confstr."
+    # os.confstr is quite a bit faster than ctypes.DLL. It's also less likely
+    # to be broken or missing. This strategy is used in the standard library
+    # platform module:
+    # https://github.com/python/cpython/blob/fcf1d003bf4f0100c9d0921ff3d70e1127ca1b71/Lib/platform.py#L175-L183
+    if sys.platform == "win32":
+        return None
+    try:
+        # os.confstr("CS_GNU_LIBC_VERSION") returns a string like "glibc 2.17":
+        _, version = os.confstr("CS_GNU_LIBC_VERSION").split()
+    except (AttributeError, OSError, ValueError):
+        # os.confstr() or CS_GNU_LIBC_VERSION not available (or a bad value)...
+        return None
+    return version
+
+
+def glibc_version_string_ctypes():
+    # type: () -> Optional[str]
+    "Fallback implementation of glibc_version_string using ctypes."
+
+    try:
+        import ctypes
+    except ImportError:
+        return None
+
+    # ctypes.CDLL(None) internally calls dlopen(NULL), and as the dlopen
+    # manpage says, "If filename is NULL, then the returned handle is for the
+    # main program". This way we can let the linker do the work to figure out
+    # which libc our process is actually using.
+    process_namespace = ctypes.CDLL(None)
+    try:
+        gnu_get_libc_version = process_namespace.gnu_get_libc_version
+    except AttributeError:
+        # Symbol doesn't exist -> therefore, we are not linked to
+        # glibc.
+        return None
+
+    # Call gnu_get_libc_version, which returns a string like "2.5"
+    gnu_get_libc_version.restype = ctypes.c_char_p
+    version_str = gnu_get_libc_version()
+    # py2 / py3 compatibility:
+    if not isinstance(version_str, str):
+        version_str = version_str.decode("ascii")
+
+    return version_str
+
+
+# platform.libc_ver regularly returns completely nonsensical glibc
+# versions. E.g. on my computer, platform says:
+#
+#   ~$ python2.7 -c 'import platform; print(platform.libc_ver())'
+#   ('glibc', '2.7')
+#   ~$ python3.5 -c 'import platform; print(platform.libc_ver())'
+#   ('glibc', '2.9')
+#
+# But the truth is:
+#
+#   ~$ ldd --version
+#   ldd (Debian GLIBC 2.22-11) 2.22
+#
+# This is unfortunate, because it means that the linehaul data on libc
+# versions that was generated by pip 8.1.2 and earlier is useless and
+# misleading. Solution: instead of using platform, use our code that actually
+# works.
+def libc_ver():
+    # type: () -> Tuple[str, str]
+    """Try to determine the glibc version
+
+    Returns a tuple of strings (lib, version) which default to empty strings
+    in case the lookup fails.
+    """
+    glibc_version = glibc_version_string()
+    if glibc_version is None:
+        return ("", "")
+    else:
+        return ("glibc", glibc_version)

env/lib/python3.8/site-packages/pip/_internal/utils/hashes.py

@@ -0,0 +1,131 @@
+from __future__ import absolute_import
+
+import hashlib
+
+from pip._vendor.six import iteritems, iterkeys, itervalues
+
+from pip._internal.exceptions import (
+    HashMismatch,
+    HashMissing,
+    InstallationError,
+)
+from pip._internal.utils.misc import read_chunks
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import (
+        Dict, List, BinaryIO, NoReturn, Iterator
+    )
+    from pip._vendor.six import PY3
+    if PY3:
+        from hashlib import _Hash
+    else:
+        from hashlib import _hash as _Hash
+
+
+# The recommended hash algo of the moment. Change this whenever the state of
+# the art changes; it won't hurt backward compatibility.
+FAVORITE_HASH = 'sha256'
+
+
+# Names of hashlib algorithms allowed by the --hash option and ``pip hash``
+# Currently, those are the ones at least as collision-resistant as sha256.
+STRONG_HASHES = ['sha256', 'sha384', 'sha512']
+
+
+class Hashes(object):
+    """A wrapper that builds multiple hashes at once and checks them against
+    known-good values
+
+    """
+    def __init__(self, hashes=None):
+        # type: (Dict[str, List[str]]) -> None
+        """
+        :param hashes: A dict of algorithm names pointing to lists of allowed
+            hex digests
+        """
+        self._allowed = {} if hashes is None else hashes
+
+    @property
+    def digest_count(self):
+        # type: () -> int
+        return sum(len(digests) for digests in self._allowed.values())
+
+    def is_hash_allowed(
+        self,
+        hash_name,   # type: str
+        hex_digest,  # type: str
+    ):
+        # type: (...) -> bool
+        """Return whether the given hex digest is allowed."""
+        return hex_digest in self._allowed.get(hash_name, [])
+
+    def check_against_chunks(self, chunks):
+        # type: (Iterator[bytes]) -> None
+        """Check good hashes against ones built from iterable of chunks of
+        data.
+
+        Raise HashMismatch if none match.
+
+        """
+        gots = {}
+        for hash_name in iterkeys(self._allowed):
+            try:
+                gots[hash_name] = hashlib.new(hash_name)
+            except (ValueError, TypeError):
+                raise InstallationError('Unknown hash name: %s' % hash_name)
+
+        for chunk in chunks:
+            for hash in itervalues(gots):
+                hash.update(chunk)
+
+        for hash_name, got in iteritems(gots):
+            if got.hexdigest() in self._allowed[hash_name]:
+                return
+        self._raise(gots)
+
+    def _raise(self, gots):
+        # type: (Dict[str, _Hash]) -> NoReturn
+        raise HashMismatch(self._allowed, gots)
+
+    def check_against_file(self, file):
+        # type: (BinaryIO) -> None
+        """Check good hashes against a file-like object
+
+        Raise HashMismatch if none match.
+
+        """
+        return self.check_against_chunks(read_chunks(file))
+
+    def check_against_path(self, path):
+        # type: (str) -> None
+        with open(path, 'rb') as file:
+            return self.check_against_file(file)
+
+    def __nonzero__(self):
+        # type: () -> bool
+        """Return whether I know any known-good hashes."""
+        return bool(self._allowed)
+
+    def __bool__(self):
+        # type: () -> bool
+        return self.__nonzero__()
+
+
+class MissingHashes(Hashes):
+    """A workalike for Hashes used when we're missing a hash for a requirement
+
+    It computes the actual hash of the requirement and raises a HashMissing
+    exception showing it to the user.
+
+    """
+    def __init__(self):
+        # type: () -> None
+        """Don't offer the ``hashes`` kwarg."""
+        # Pass our favorite hash in to generate a "gotten hash". With the
+        # empty list, it will never match, so an error will always raise.
+        super(MissingHashes, self).__init__(hashes={FAVORITE_HASH: []})
+
+    def _raise(self, gots):
+        # type: (Dict[str, _Hash]) -> NoReturn
+        raise HashMissing(gots[FAVORITE_HASH].hexdigest())

env/lib/python3.8/site-packages/pip/_internal/utils/inject_securetransport.py

@@ -0,0 +1,36 @@
+"""A helper module that injects SecureTransport, on import.
+
+The import should be done as early as possible, to ensure all requests and
+sessions (or whatever) are created after injecting SecureTransport.
+
+Note that we only do the injection on macOS, when the linked OpenSSL is too
+old to handle TLSv1.2.
+"""
+
+import sys
+
+
+def inject_securetransport():
+    # type: () -> None
+    # Only relevant on macOS
+    if sys.platform != "darwin":
+        return
+
+    try:
+        import ssl
+    except ImportError:
+        return
+
+    # Checks for OpenSSL 1.0.1
+    if ssl.OPENSSL_VERSION_NUMBER >= 0x1000100f:
+        return
+
+    try:
+        from pip._vendor.urllib3.contrib import securetransport
+    except (ImportError, OSError):
+        return
+
+    securetransport.inject_into_urllib3()
+
+
+inject_securetransport()

env/lib/python3.8/site-packages/pip/_internal/utils/logging.py

@@ -0,0 +1,398 @@
+# The following comment should be removed at some point in the future.
+# mypy: disallow-untyped-defs=False
+
+from __future__ import absolute_import
+
+import contextlib
+import errno
+import logging
+import logging.handlers
+import os
+import sys
+from logging import Filter, getLogger
+
+from pip._vendor.six import PY2
+
+from pip._internal.utils.compat import WINDOWS
+from pip._internal.utils.deprecation import DEPRECATION_MSG_PREFIX
+from pip._internal.utils.misc import ensure_dir
+
+try:
+    import threading
+except ImportError:
+    import dummy_threading as threading  # type: ignore
+
+
+try:
+    # Use "import as" and set colorama in the else clause to avoid mypy
+    # errors and get the following correct revealed type for colorama:
+    # `Union[_importlib_modulespec.ModuleType, None]`
+    # Otherwise, we get an error like the following in the except block:
+    #  > Incompatible types in assignment (expression has type "None",
+    #   variable has type Module)
+    # TODO: eliminate the need to use "import as" once mypy addresses some
+    #  of its issues with conditional imports. Here is an umbrella issue:
+    #  https://github.com/python/mypy/issues/1297
+    from pip._vendor import colorama as _colorama
+# Lots of different errors can come from this, including SystemError and
+# ImportError.
+except Exception:
+    colorama = None
+else:
+    # Import Fore explicitly rather than accessing below as colorama.Fore
+    # to avoid the following error running mypy:
+    # > Module has no attribute "Fore"
+    # TODO: eliminate the need to import Fore once mypy addresses some of its
+    #  issues with conditional imports. This particular case could be an
+    #  instance of the following issue (but also see the umbrella issue above):
+    #  https://github.com/python/mypy/issues/3500
+    from pip._vendor.colorama import Fore
+
+    colorama = _colorama
+
+
+_log_state = threading.local()
+_log_state.indentation = 0
+subprocess_logger = getLogger('pip.subprocessor')
+
+
+class BrokenStdoutLoggingError(Exception):
+    """
+    Raised if BrokenPipeError occurs for the stdout stream while logging.
+    """
+    pass
+
+
+# BrokenPipeError does not exist in Python 2 and, in addition, manifests
+# differently in Windows and non-Windows.
+if WINDOWS:
+    # In Windows, a broken pipe can show up as EINVAL rather than EPIPE:
+    # https://bugs.python.org/issue19612
+    # https://bugs.python.org/issue30418
+    if PY2:
+        def _is_broken_pipe_error(exc_class, exc):
+            """See the docstring for non-Windows Python 3 below."""
+            return (exc_class is IOError and
+                    exc.errno in (errno.EINVAL, errno.EPIPE))
+    else:
+        # In Windows, a broken pipe IOError became OSError in Python 3.
+        def _is_broken_pipe_error(exc_class, exc):
+            """See the docstring for non-Windows Python 3 below."""
+            return ((exc_class is BrokenPipeError) or  # noqa: F821
+                    (exc_class is OSError and
+                     exc.errno in (errno.EINVAL, errno.EPIPE)))
+elif PY2:
+    def _is_broken_pipe_error(exc_class, exc):
+        """See the docstring for non-Windows Python 3 below."""
+        return (exc_class is IOError and exc.errno == errno.EPIPE)
+else:
+    # Then we are in the non-Windows Python 3 case.
+    def _is_broken_pipe_error(exc_class, exc):
+        """
+        Return whether an exception is a broken pipe error.
+
+        Args:
+          exc_class: an exception class.
+          exc: an exception instance.
+        """
+        return (exc_class is BrokenPipeError)  # noqa: F821
+
+
+@contextlib.contextmanager
+def indent_log(num=2):
+    """
+    A context manager which will cause the log output to be indented for any
+    log messages emitted inside it.
+    """
+    _log_state.indentation += num
+    try:
+        yield
+    finally:
+        _log_state.indentation -= num
+
+
+def get_indentation():
+    return getattr(_log_state, 'indentation', 0)
+
+
+class IndentingFormatter(logging.Formatter):
+
+    def __init__(self, *args, **kwargs):
+        """
+        A logging.Formatter that obeys the indent_log() context manager.
+
+        :param add_timestamp: A bool indicating output lines should be prefixed
+            with their record's timestamp.
+        """
+        self.add_timestamp = kwargs.pop("add_timestamp", False)
+        super(IndentingFormatter, self).__init__(*args, **kwargs)
+
+    def get_message_start(self, formatted, levelno):
+        """
+        Return the start of the formatted log message (not counting the
+        prefix to add to each line).
+        """
+        if levelno < logging.WARNING:
+            return ''
+        if formatted.startswith(DEPRECATION_MSG_PREFIX):
+            # Then the message already has a prefix.  We don't want it to
+            # look like "WARNING: DEPRECATION: ...."
+            return ''
+        if levelno < logging.ERROR:
+            return 'WARNING: '
+
+        return 'ERROR: '
+
+    def format(self, record):
+        """
+        Calls the standard formatter, but will indent all of the log message
+        lines by our current indentation level.
+        """
+        formatted = super(IndentingFormatter, self).format(record)
+        message_start = self.get_message_start(formatted, record.levelno)
+        formatted = message_start + formatted
+
+        prefix = ''
+        if self.add_timestamp:
+            # TODO: Use Formatter.default_time_format after dropping PY2.
+            t = self.formatTime(record, "%Y-%m-%dT%H:%M:%S")
+            prefix = '%s,%03d ' % (t, record.msecs)
+        prefix += " " * get_indentation()
+        formatted = "".join([
+            prefix + line
+            for line in formatted.splitlines(True)
+        ])
+        return formatted
+
+
+def _color_wrap(*colors):
+    def wrapped(inp):
+        return "".join(list(colors) + [inp, colorama.Style.RESET_ALL])
+    return wrapped
+
+
+class ColorizedStreamHandler(logging.StreamHandler):
+
+    # Don't build up a list of colors if we don't have colorama
+    if colorama:
+        COLORS = [
+            # This needs to be in order from highest logging level to lowest.
+            (logging.ERROR, _color_wrap(Fore.RED)),
+            (logging.WARNING, _color_wrap(Fore.YELLOW)),
+        ]
+    else:
+        COLORS = []
+
+    def __init__(self, stream=None, no_color=None):
+        logging.StreamHandler.__init__(self, stream)
+        self._no_color = no_color
+
+        if WINDOWS and colorama:
+            self.stream = colorama.AnsiToWin32(self.stream)
+
+    def _using_stdout(self):
+        """
+        Return whether the handler is using sys.stdout.
+        """
+        if WINDOWS and colorama:
+            # Then self.stream is an AnsiToWin32 object.
+            return self.stream.wrapped is sys.stdout
+
+        return self.stream is sys.stdout
+
+    def should_color(self):
+        # Don't colorize things if we do not have colorama or if told not to
+        if not colorama or self._no_color:
+            return False
+
+        real_stream = (
+            self.stream if not isinstance(self.stream, colorama.AnsiToWin32)
+            else self.stream.wrapped
+        )
+
+        # If the stream is a tty we should color it
+        if hasattr(real_stream, "isatty") and real_stream.isatty():
+            return True
+
+        # If we have an ANSI term we should color it
+        if os.environ.get("TERM") == "ANSI":
+            return True
+
+        # If anything else we should not color it
+        return False
+
+    def format(self, record):
+        msg = logging.StreamHandler.format(self, record)
+
+        if self.should_color():
+            for level, color in self.COLORS:
+                if record.levelno >= level:
+                    msg = color(msg)
+                    break
+
+        return msg
+
+    # The logging module says handleError() can be customized.
+    def handleError(self, record):
+        exc_class, exc = sys.exc_info()[:2]
+        # If a broken pipe occurred while calling write() or flush() on the
+        # stdout stream in logging's Handler.emit(), then raise our special
+        # exception so we can handle it in main() instead of logging the
+        # broken pipe error and continuing.
+        if (exc_class and self._using_stdout() and
+                _is_broken_pipe_error(exc_class, exc)):
+            raise BrokenStdoutLoggingError()
+
+        return super(ColorizedStreamHandler, self).handleError(record)
+
+
+class BetterRotatingFileHandler(logging.handlers.RotatingFileHandler):
+
+    def _open(self):
+        ensure_dir(os.path.dirname(self.baseFilename))
+        return logging.handlers.RotatingFileHandler._open(self)
+
+
+class MaxLevelFilter(Filter):
+
+    def __init__(self, level):
+        self.level = level
+
+    def filter(self, record):
+        return record.levelno < self.level
+
+
+class ExcludeLoggerFilter(Filter):
+
+    """
+    A logging Filter that excludes records from a logger (or its children).
+    """
+
+    def filter(self, record):
+        # The base Filter class allows only records from a logger (or its
+        # children).
+        return not super(ExcludeLoggerFilter, self).filter(record)
+
+
+def setup_logging(verbosity, no_color, user_log_file):
+    """Configures and sets up all of the logging
+
+    Returns the requested logging level, as its integer value.
+    """
+
+    # Determine the level to be logging at.
+    if verbosity >= 1:
+        level = "DEBUG"
+    elif verbosity == -1:
+        level = "WARNING"
+    elif verbosity == -2:
+        level = "ERROR"
+    elif verbosity <= -3:
+        level = "CRITICAL"
+    else:
+        level = "INFO"
+
+    level_number = getattr(logging, level)
+
+    # The "root" logger should match the "console" level *unless* we also need
+    # to log to a user log file.
+    include_user_log = user_log_file is not None
+    if include_user_log:
+        additional_log_file = user_log_file
+        root_level = "DEBUG"
+    else:
+        additional_log_file = "/dev/null"
+        root_level = level
+
+    # Disable any logging besides WARNING unless we have DEBUG level logging
+    # enabled for vendored libraries.
+    vendored_log_level = "WARNING" if level in ["INFO", "ERROR"] else "DEBUG"
+
+    # Shorthands for clarity
+    log_streams = {
+        "stdout": "ext://sys.stdout",
+        "stderr": "ext://sys.stderr",
+    }
+    handler_classes = {
+        "stream": "pip._internal.utils.logging.ColorizedStreamHandler",
+        "file": "pip._internal.utils.logging.BetterRotatingFileHandler",
+    }
+    handlers = ["console", "console_errors", "console_subprocess"] + (
+        ["user_log"] if include_user_log else []
+    )
+
+    logging.config.dictConfig({
+        "version": 1,
+        "disable_existing_loggers": False,
+        "filters": {
+            "exclude_warnings": {
+                "()": "pip._internal.utils.logging.MaxLevelFilter",
+                "level": logging.WARNING,
+            },
+            "restrict_to_subprocess": {
+                "()": "logging.Filter",
+                "name": subprocess_logger.name,
+            },
+            "exclude_subprocess": {
+                "()": "pip._internal.utils.logging.ExcludeLoggerFilter",
+                "name": subprocess_logger.name,
+            },
+        },
+        "formatters": {
+            "indent": {
+                "()": IndentingFormatter,
+                "format": "%(message)s",
+            },
+            "indent_with_timestamp": {
+                "()": IndentingFormatter,
+                "format": "%(message)s",
+                "add_timestamp": True,
+            },
+        },
+        "handlers": {
+            "console": {
+                "level": level,
+                "class": handler_classes["stream"],
+                "no_color": no_color,
+                "stream": log_streams["stdout"],
+                "filters": ["exclude_subprocess", "exclude_warnings"],
+                "formatter": "indent",
+            },
+            "console_errors": {
+                "level": "WARNING",
+                "class": handler_classes["stream"],
+                "no_color": no_color,
+                "stream": log_streams["stderr"],
+                "filters": ["exclude_subprocess"],
+                "formatter": "indent",
+            },
+            # A handler responsible for logging to the console messages
+            # from the "subprocessor" logger.
+            "console_subprocess": {
+                "level": level,
+                "class": handler_classes["stream"],
+                "no_color": no_color,
+                "stream": log_streams["stderr"],
+                "filters": ["restrict_to_subprocess"],
+                "formatter": "indent",
+            },
+            "user_log": {
+                "level": "DEBUG",
+                "class": handler_classes["file"],
+                "filename": additional_log_file,
+                "delay": True,
+                "formatter": "indent_with_timestamp",
+            },
+        },
+        "root": {
+            "level": root_level,
+            "handlers": handlers,
+        },
+        "loggers": {
+            "pip._vendor": {
+                "level": vendored_log_level
+            }
+        },
+    })
+
+    return level_number

env/lib/python3.8/site-packages/pip/_internal/utils/marker_files.py

@@ -0,0 +1,25 @@
+import os.path
+
+DELETE_MARKER_MESSAGE = '''\
+This file is placed here by pip to indicate the source was put
+here by pip.
+
+Once this package is successfully installed this source code will be
+deleted (unless you remove this file).
+'''
+PIP_DELETE_MARKER_FILENAME = 'pip-delete-this-directory.txt'
+
+
+def has_delete_marker_file(directory):
+    # type: (str) -> bool
+    return os.path.exists(os.path.join(directory, PIP_DELETE_MARKER_FILENAME))
+
+
+def write_delete_marker_file(directory):
+    # type: (str) -> None
+    """
+    Write the pip delete marker file into this directory.
+    """
+    filepath = os.path.join(directory, PIP_DELETE_MARKER_FILENAME)
+    with open(filepath, 'w') as marker_fp:
+        marker_fp.write(DELETE_MARKER_MESSAGE)

env/lib/python3.8/site-packages/pip/_internal/utils/misc.py

@@ -0,0 +1,904 @@
+# The following comment should be removed at some point in the future.
+# mypy: strict-optional=False
+# mypy: disallow-untyped-defs=False
+
+from __future__ import absolute_import
+
+import contextlib
+import errno
+import getpass
+import hashlib
+import io
+import logging
+import os
+import posixpath
+import shutil
+import stat
+import sys
+from collections import deque
+
+from pip._vendor import pkg_resources
+# NOTE: retrying is not annotated in typeshed as on 2017-07-17, which is
+#       why we ignore the type on this import.
+from pip._vendor.retrying import retry  # type: ignore
+from pip._vendor.six import PY2, text_type
+from pip._vendor.six.moves import input
+from pip._vendor.six.moves.urllib import parse as urllib_parse
+from pip._vendor.six.moves.urllib.parse import unquote as urllib_unquote
+
+from pip import __version__
+from pip._internal.exceptions import CommandError
+from pip._internal.locations import (
+    get_major_minor_version,
+    site_packages,
+    user_site,
+)
+from pip._internal.utils.compat import (
+    WINDOWS,
+    expanduser,
+    stdlib_pkgs,
+    str_to_display,
+)
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING, cast
+from pip._internal.utils.virtualenv import (
+    running_under_virtualenv,
+    virtualenv_no_global,
+)
+
+if PY2:
+    from io import BytesIO as StringIO
+else:
+    from io import StringIO
+
+if MYPY_CHECK_RUNNING:
+    from typing import (
+        Any, AnyStr, Container, Iterable, List, Optional, Text,
+        Tuple, Union,
+    )
+    from pip._vendor.pkg_resources import Distribution
+
+    VersionInfo = Tuple[int, int, int]
+
+
+__all__ = ['rmtree', 'display_path', 'backup_dir',
+           'ask', 'splitext',
+           'format_size', 'is_installable_dir',
+           'normalize_path',
+           'renames', 'get_prog',
+           'captured_stdout', 'ensure_dir',
+           'get_installed_version', 'remove_auth_from_url']
+
+
+logger = logging.getLogger(__name__)
+
+
+def get_pip_version():
+    # type: () -> str
+    pip_pkg_dir = os.path.join(os.path.dirname(__file__), "..", "..")
+    pip_pkg_dir = os.path.abspath(pip_pkg_dir)
+
+    return (
+        'pip {} from {} (python {})'.format(
+            __version__, pip_pkg_dir, get_major_minor_version(),
+        )
+    )
+
+
+def normalize_version_info(py_version_info):
+    # type: (Tuple[int, ...]) -> Tuple[int, int, int]
+    """
+    Convert a tuple of ints representing a Python version to one of length
+    three.
+
+    :param py_version_info: a tuple of ints representing a Python version,
+        or None to specify no version. The tuple can have any length.
+
+    :return: a tuple of length three if `py_version_info` is non-None.
+        Otherwise, return `py_version_info` unchanged (i.e. None).
+    """
+    if len(py_version_info) < 3:
+        py_version_info += (3 - len(py_version_info)) * (0,)
+    elif len(py_version_info) > 3:
+        py_version_info = py_version_info[:3]
+
+    return cast('VersionInfo', py_version_info)
+
+
+def ensure_dir(path):
+    # type: (AnyStr) -> None
+    """os.path.makedirs without EEXIST."""
+    try:
+        os.makedirs(path)
+    except OSError as e:
+        # Windows can raise spurious ENOTEMPTY errors. See #6426.
+        if e.errno != errno.EEXIST and e.errno != errno.ENOTEMPTY:
+            raise
+
+
+def get_prog():
+    # type: () -> str
+    try:
+        prog = os.path.basename(sys.argv[0])
+        if prog in ('__main__.py', '-c'):
+            return "%s -m pip" % sys.executable
+        else:
+            return prog
+    except (AttributeError, TypeError, IndexError):
+        pass
+    return 'pip'
+
+
+# Retry every half second for up to 3 seconds
+@retry(stop_max_delay=3000, wait_fixed=500)
+def rmtree(dir, ignore_errors=False):
+    # type: (str, bool) -> None
+    shutil.rmtree(dir, ignore_errors=ignore_errors,
+                  onerror=rmtree_errorhandler)
+
+
+def rmtree_errorhandler(func, path, exc_info):
+    """On Windows, the files in .svn are read-only, so when rmtree() tries to
+    remove them, an exception is thrown.  We catch that here, remove the
+    read-only attribute, and hopefully continue without problems."""
+    try:
+        has_attr_readonly = not (os.stat(path).st_mode & stat.S_IWRITE)
+    except (IOError, OSError):
+        # it's equivalent to os.path.exists
+        return
+
+    if has_attr_readonly:
+        # convert to read/write
+        os.chmod(path, stat.S_IWRITE)
+        # use the original function to repeat the operation
+        func(path)
+        return
+    else:
+        raise
+
+
+def path_to_display(path):
+    # type: (Optional[Union[str, Text]]) -> Optional[Text]
+    """
+    Convert a bytes (or text) path to text (unicode in Python 2) for display
+    and logging purposes.
+
+    This function should never error out. Also, this function is mainly needed
+    for Python 2 since in Python 3 str paths are already text.
+    """
+    if path is None:
+        return None
+    if isinstance(path, text_type):
+        return path
+    # Otherwise, path is a bytes object (str in Python 2).
+    try:
+        display_path = path.decode(sys.getfilesystemencoding(), 'strict')
+    except UnicodeDecodeError:
+        # Include the full bytes to make troubleshooting easier, even though
+        # it may not be very human readable.
+        if PY2:
+            # Convert the bytes to a readable str representation using
+            # repr(), and then convert the str to unicode.
+            #   Also, we add the prefix "b" to the repr() return value both
+            # to make the Python 2 output look like the Python 3 output, and
+            # to signal to the user that this is a bytes representation.
+            display_path = str_to_display('b{!r}'.format(path))
+        else:
+            # Silence the "F821 undefined name 'ascii'" flake8 error since
+            # in Python 3 ascii() is a built-in.
+            display_path = ascii(path)  # noqa: F821
+
+    return display_path
+
+
+def display_path(path):
+    # type: (Union[str, Text]) -> str
+    """Gives the display value for a given path, making it relative to cwd
+    if possible."""
+    path = os.path.normcase(os.path.abspath(path))
+    if sys.version_info[0] == 2:
+        path = path.decode(sys.getfilesystemencoding(), 'replace')
+        path = path.encode(sys.getdefaultencoding(), 'replace')
+    if path.startswith(os.getcwd() + os.path.sep):
+        path = '.' + path[len(os.getcwd()):]
+    return path
+
+
+def backup_dir(dir, ext='.bak'):
+    # type: (str, str) -> str
+    """Figure out the name of a directory to back up the given dir to
+    (adding .bak, .bak2, etc)"""
+    n = 1
+    extension = ext
+    while os.path.exists(dir + extension):
+        n += 1
+        extension = ext + str(n)
+    return dir + extension
+
+
+def ask_path_exists(message, options):
+    # type: (str, Iterable[str]) -> str
+    for action in os.environ.get('PIP_EXISTS_ACTION', '').split():
+        if action in options:
+            return action
+    return ask(message, options)
+
+
+def _check_no_input(message):
+    # type: (str) -> None
+    """Raise an error if no input is allowed."""
+    if os.environ.get('PIP_NO_INPUT'):
+        raise Exception(
+            'No input was expected ($PIP_NO_INPUT set); question: %s' %
+            message
+        )
+
+
+def ask(message, options):
+    # type: (str, Iterable[str]) -> str
+    """Ask the message interactively, with the given possible responses"""
+    while 1:
+        _check_no_input(message)
+        response = input(message)
+        response = response.strip().lower()
+        if response not in options:
+            print(
+                'Your response (%r) was not one of the expected responses: '
+                '%s' % (response, ', '.join(options))
+            )
+        else:
+            return response
+
+
+def ask_input(message):
+    # type: (str) -> str
+    """Ask for input interactively."""
+    _check_no_input(message)
+    return input(message)
+
+
+def ask_password(message):
+    # type: (str) -> str
+    """Ask for a password interactively."""
+    _check_no_input(message)
+    return getpass.getpass(message)
+
+
+def format_size(bytes):
+    # type: (float) -> str
+    if bytes > 1000 * 1000:
+        return '%.1f MB' % (bytes / 1000.0 / 1000)
+    elif bytes > 10 * 1000:
+        return '%i kB' % (bytes / 1000)
+    elif bytes > 1000:
+        return '%.1f kB' % (bytes / 1000.0)
+    else:
+        return '%i bytes' % bytes
+
+
+def is_installable_dir(path):
+    # type: (str) -> bool
+    """Is path is a directory containing setup.py or pyproject.toml?
+    """
+    if not os.path.isdir(path):
+        return False
+    setup_py = os.path.join(path, 'setup.py')
+    if os.path.isfile(setup_py):
+        return True
+    pyproject_toml = os.path.join(path, 'pyproject.toml')
+    if os.path.isfile(pyproject_toml):
+        return True
+    return False
+
+
+def read_chunks(file, size=io.DEFAULT_BUFFER_SIZE):
+    """Yield pieces of data from a file-like object until EOF."""
+    while True:
+        chunk = file.read(size)
+        if not chunk:
+            break
+        yield chunk
+
+
+def normalize_path(path, resolve_symlinks=True):
+    # type: (str, bool) -> str
+    """
+    Convert a path to its canonical, case-normalized, absolute version.
+
+    """
+    path = expanduser(path)
+    if resolve_symlinks:
+        path = os.path.realpath(path)
+    else:
+        path = os.path.abspath(path)
+    return os.path.normcase(path)
+
+
+def splitext(path):
+    # type: (str) -> Tuple[str, str]
+    """Like os.path.splitext, but take off .tar too"""
+    base, ext = posixpath.splitext(path)
+    if base.lower().endswith('.tar'):
+        ext = base[-4:] + ext
+        base = base[:-4]
+    return base, ext
+
+
+def renames(old, new):
+    # type: (str, str) -> None
+    """Like os.renames(), but handles renaming across devices."""
+    # Implementation borrowed from os.renames().
+    head, tail = os.path.split(new)
+    if head and tail and not os.path.exists(head):
+        os.makedirs(head)
+
+    shutil.move(old, new)
+
+    head, tail = os.path.split(old)
+    if head and tail:
+        try:
+            os.removedirs(head)
+        except OSError:
+            pass
+
+
+def is_local(path):
+    # type: (str) -> bool
+    """
+    Return True if this is a path pip is allowed to modify.
+
+    If we're in a virtualenv, sys.prefix points to the virtualenv's
+    prefix; only sys.prefix is considered local.
+
+    If we're not in a virtualenv, in general we can modify anything.
+    However, if the OS vendor has configured distutils to install
+    somewhere other than sys.prefix (which could be a subdirectory of
+    sys.prefix, e.g. /usr/local), we consider sys.prefix itself nonlocal
+    and the domain of the OS vendor. (In other words, everything _other
+    than_ sys.prefix is considered local.)
+
+    Caution: this function assumes the head of path has been normalized
+    with normalize_path.
+    """
+
+    path = normalize_path(path)
+    prefix = normalize_path(sys.prefix)
+
+    if running_under_virtualenv():
+        return path.startswith(normalize_path(sys.prefix))
+    else:
+        from pip._internal.locations import distutils_scheme
+        if path.startswith(prefix):
+            for local_path in distutils_scheme("").values():
+                if path.startswith(normalize_path(local_path)):
+                    return True
+            return False
+        else:
+            return True
+
+
+def dist_is_local(dist):
+    # type: (Distribution) -> bool
+    """
+    Return True if given Distribution object is installed somewhere pip
+    is allowed to modify.
+
+    """
+    return is_local(dist_location(dist))
+
+
+def dist_in_usersite(dist):
+    # type: (Distribution) -> bool
+    """
+    Return True if given Distribution is installed in user site.
+    """
+    return dist_location(dist).startswith(normalize_path(user_site))
+
+
+def dist_in_site_packages(dist):
+    # type: (Distribution) -> bool
+    """
+    Return True if given Distribution is installed in
+    sysconfig.get_python_lib().
+    """
+    return dist_location(dist).startswith(normalize_path(site_packages))
+
+
+def dist_is_editable(dist):
+    # type: (Distribution) -> bool
+    """
+    Return True if given Distribution is an editable install.
+    """
+    for path_item in sys.path:
+        egg_link = os.path.join(path_item, dist.project_name + '.egg-link')
+        if os.path.isfile(egg_link):
+            return True
+    return False
+
+
+def get_installed_distributions(
+        local_only=True,  # type: bool
+        skip=stdlib_pkgs,  # type: Container[str]
+        include_editables=True,  # type: bool
+        editables_only=False,  # type: bool
+        user_only=False,  # type: bool
+        paths=None  # type: Optional[List[str]]
+):
+    # type: (...) -> List[Distribution]
+    """
+    Return a list of installed Distribution objects.
+
+    If ``local_only`` is True (default), only return installations
+    local to the current virtualenv, if in a virtualenv.
+
+    ``skip`` argument is an iterable of lower-case project names to
+    ignore; defaults to stdlib_pkgs
+
+    If ``include_editables`` is False, don't report editables.
+
+    If ``editables_only`` is True , only report editables.
+
+    If ``user_only`` is True , only report installations in the user
+    site directory.
+
+    If ``paths`` is set, only report the distributions present at the
+    specified list of locations.
+    """
+    if paths:
+        working_set = pkg_resources.WorkingSet(paths)
+    else:
+        working_set = pkg_resources.working_set
+
+    if local_only:
+        local_test = dist_is_local
+    else:
+        def local_test(d):
+            return True
+
+    if include_editables:
+        def editable_test(d):
+            return True
+    else:
+        def editable_test(d):
+            return not dist_is_editable(d)
+
+    if editables_only:
+        def editables_only_test(d):
+            return dist_is_editable(d)
+    else:
+        def editables_only_test(d):
+            return True
+
+    if user_only:
+        user_test = dist_in_usersite
+    else:
+        def user_test(d):
+            return True
+
+    return [d for d in working_set
+            if local_test(d) and
+            d.key not in skip and
+            editable_test(d) and
+            editables_only_test(d) and
+            user_test(d)
+            ]
+
+
+def egg_link_path(dist):
+    # type: (Distribution) -> Optional[str]
+    """
+    Return the path for the .egg-link file if it exists, otherwise, None.
+
+    There's 3 scenarios:
+    1) not in a virtualenv
+       try to find in site.USER_SITE, then site_packages
+    2) in a no-global virtualenv
+       try to find in site_packages
+    3) in a yes-global virtualenv
+       try to find in site_packages, then site.USER_SITE
+       (don't look in global location)
+
+    For #1 and #3, there could be odd cases, where there's an egg-link in 2
+    locations.
+
+    This method will just return the first one found.
+    """
+    sites = []
+    if running_under_virtualenv():
+        sites.append(site_packages)
+        if not virtualenv_no_global() and user_site:
+            sites.append(user_site)
+    else:
+        if user_site:
+            sites.append(user_site)
+        sites.append(site_packages)
+
+    for site in sites:
+        egglink = os.path.join(site, dist.project_name) + '.egg-link'
+        if os.path.isfile(egglink):
+            return egglink
+    return None
+
+
+def dist_location(dist):
+    # type: (Distribution) -> str
+    """
+    Get the site-packages location of this distribution. Generally
+    this is dist.location, except in the case of develop-installed
+    packages, where dist.location is the source code location, and we
+    want to know where the egg-link file is.
+
+    The returned location is normalized (in particular, with symlinks removed).
+    """
+    egg_link = egg_link_path(dist)
+    if egg_link:
+        return normalize_path(egg_link)
+    return normalize_path(dist.location)
+
+
+def write_output(msg, *args):
+    # type: (str, str) -> None
+    logger.info(msg, *args)
+
+
+class FakeFile(object):
+    """Wrap a list of lines in an object with readline() to make
+    ConfigParser happy."""
+    def __init__(self, lines):
+        self._gen = (l for l in lines)
+
+    def readline(self):
+        try:
+            try:
+                return next(self._gen)
+            except NameError:
+                return self._gen.next()
+        except StopIteration:
+            return ''
+
+    def __iter__(self):
+        return self._gen
+
+
+class StreamWrapper(StringIO):
+
+    @classmethod
+    def from_stream(cls, orig_stream):
+        cls.orig_stream = orig_stream
+        return cls()
+
+    # compileall.compile_dir() needs stdout.encoding to print to stdout
+    @property
+    def encoding(self):
+        return self.orig_stream.encoding
+
+
+@contextlib.contextmanager
+def captured_output(stream_name):
+    """Return a context manager used by captured_stdout/stdin/stderr
+    that temporarily replaces the sys stream *stream_name* with a StringIO.
+
+    Taken from Lib/support/__init__.py in the CPython repo.
+    """
+    orig_stdout = getattr(sys, stream_name)
+    setattr(sys, stream_name, StreamWrapper.from_stream(orig_stdout))
+    try:
+        yield getattr(sys, stream_name)
+    finally:
+        setattr(sys, stream_name, orig_stdout)
+
+
+def captured_stdout():
+    """Capture the output of sys.stdout:
+
+       with captured_stdout() as stdout:
+           print('hello')
+       self.assertEqual(stdout.getvalue(), 'hello\n')
+
+    Taken from Lib/support/__init__.py in the CPython repo.
+    """
+    return captured_output('stdout')
+
+
+def captured_stderr():
+    """
+    See captured_stdout().
+    """
+    return captured_output('stderr')
+
+
+class cached_property(object):
+    """A property that is only computed once per instance and then replaces
+       itself with an ordinary attribute. Deleting the attribute resets the
+       property.
+
+       Source: https://github.com/bottlepy/bottle/blob/0.11.5/bottle.py#L175
+    """
+
+    def __init__(self, func):
+        self.__doc__ = getattr(func, '__doc__')
+        self.func = func
+
+    def __get__(self, obj, cls):
+        if obj is None:
+            # We're being accessed from the class itself, not from an object
+            return self
+        value = obj.__dict__[self.func.__name__] = self.func(obj)
+        return value
+
+
+def get_installed_version(dist_name, working_set=None):
+    """Get the installed version of dist_name avoiding pkg_resources cache"""
+    # Create a requirement that we'll look for inside of setuptools.
+    req = pkg_resources.Requirement.parse(dist_name)
+
+    if working_set is None:
+        # We want to avoid having this cached, so we need to construct a new
+        # working set each time.
+        working_set = pkg_resources.WorkingSet()
+
+    # Get the installed distribution from our working set
+    dist = working_set.find(req)
+
+    # Check to see if we got an installed distribution or not, if we did
+    # we want to return it's version.
+    return dist.version if dist else None
+
+
+def consume(iterator):
+    """Consume an iterable at C speed."""
+    deque(iterator, maxlen=0)
+
+
+# Simulates an enum
+def enum(*sequential, **named):
+    enums = dict(zip(sequential, range(len(sequential))), **named)
+    reverse = {value: key for key, value in enums.items()}
+    enums['reverse_mapping'] = reverse
+    return type('Enum', (), enums)
+
+
+def build_netloc(host, port):
+    # type: (str, Optional[int]) -> str
+    """
+    Build a netloc from a host-port pair
+    """
+    if port is None:
+        return host
+    if ':' in host:
+        # Only wrap host with square brackets when it is IPv6
+        host = '[{}]'.format(host)
+    return '{}:{}'.format(host, port)
+
+
+def build_url_from_netloc(netloc, scheme='https'):
+    # type: (str, str) -> str
+    """
+    Build a full URL from a netloc.
+    """
+    if netloc.count(':') >= 2 and '@' not in netloc and '[' not in netloc:
+        # It must be a bare IPv6 address, so wrap it with brackets.
+        netloc = '[{}]'.format(netloc)
+    return '{}://{}'.format(scheme, netloc)
+
+
+def parse_netloc(netloc):
+    # type: (str) -> Tuple[str, Optional[int]]
+    """
+    Return the host-port pair from a netloc.
+    """
+    url = build_url_from_netloc(netloc)
+    parsed = urllib_parse.urlparse(url)
+    return parsed.hostname, parsed.port
+
+
+def split_auth_from_netloc(netloc):
+    """
+    Parse out and remove the auth information from a netloc.
+
+    Returns: (netloc, (username, password)).
+    """
+    if '@' not in netloc:
+        return netloc, (None, None)
+
+    # Split from the right because that's how urllib.parse.urlsplit()
+    # behaves if more than one @ is present (which can be checked using
+    # the password attribute of urlsplit()'s return value).
+    auth, netloc = netloc.rsplit('@', 1)
+    if ':' in auth:
+        # Split from the left because that's how urllib.parse.urlsplit()
+        # behaves if more than one : is present (which again can be checked
+        # using the password attribute of the return value)
+        user_pass = auth.split(':', 1)
+    else:
+        user_pass = auth, None
+
+    user_pass = tuple(
+        None if x is None else urllib_unquote(x) for x in user_pass
+    )
+
+    return netloc, user_pass
+
+
+def redact_netloc(netloc):
+    # type: (str) -> str
+    """
+    Replace the sensitive data in a netloc with "****", if it exists.
+
+    For example:
+        - "user:pass@example.com" returns "user:****@example.com"
+        - "accesstoken@example.com" returns "****@example.com"
+    """
+    netloc, (user, password) = split_auth_from_netloc(netloc)
+    if user is None:
+        return netloc
+    if password is None:
+        user = '****'
+        password = ''
+    else:
+        user = urllib_parse.quote(user)
+        password = ':****'
+    return '{user}{password}@{netloc}'.format(user=user,
+                                              password=password,
+                                              netloc=netloc)
+
+
+def _transform_url(url, transform_netloc):
+    """Transform and replace netloc in a url.
+
+    transform_netloc is a function taking the netloc and returning a
+    tuple. The first element of this tuple is the new netloc. The
+    entire tuple is returned.
+
+    Returns a tuple containing the transformed url as item 0 and the
+    original tuple returned by transform_netloc as item 1.
+    """
+    purl = urllib_parse.urlsplit(url)
+    netloc_tuple = transform_netloc(purl.netloc)
+    # stripped url
+    url_pieces = (
+        purl.scheme, netloc_tuple[0], purl.path, purl.query, purl.fragment
+    )
+    surl = urllib_parse.urlunsplit(url_pieces)
+    return surl, netloc_tuple
+
+
+def _get_netloc(netloc):
+    return split_auth_from_netloc(netloc)
+
+
+def _redact_netloc(netloc):
+    return (redact_netloc(netloc),)
+
+
+def split_auth_netloc_from_url(url):
+    # type: (str) -> Tuple[str, str, Tuple[str, str]]
+    """
+    Parse a url into separate netloc, auth, and url with no auth.
+
+    Returns: (url_without_auth, netloc, (username, password))
+    """
+    url_without_auth, (netloc, auth) = _transform_url(url, _get_netloc)
+    return url_without_auth, netloc, auth
+
+
+def remove_auth_from_url(url):
+    # type: (str) -> str
+    """Return a copy of url with 'username:password@' removed."""
+    # username/pass params are passed to subversion through flags
+    # and are not recognized in the url.
+    return _transform_url(url, _get_netloc)[0]
+
+
+def redact_auth_from_url(url):
+    # type: (str) -> str
+    """Replace the password in a given url with ****."""
+    return _transform_url(url, _redact_netloc)[0]
+
+
+class HiddenText(object):
+    def __init__(
+        self,
+        secret,    # type: str
+        redacted,  # type: str
+    ):
+        # type: (...) -> None
+        self.secret = secret
+        self.redacted = redacted
+
+    def __repr__(self):
+        # type: (...) -> str
+        return '<HiddenText {!r}>'.format(str(self))
+
+    def __str__(self):
+        # type: (...) -> str
+        return self.redacted
+
+    # This is useful for testing.
+    def __eq__(self, other):
+        # type: (Any) -> bool
+        if type(self) != type(other):
+            return False
+
+        # The string being used for redaction doesn't also have to match,
+        # just the raw, original string.
+        return (self.secret == other.secret)
+
+    # We need to provide an explicit __ne__ implementation for Python 2.
+    # TODO: remove this when we drop PY2 support.
+    def __ne__(self, other):
+        # type: (Any) -> bool
+        return not self == other
+
+
+def hide_value(value):
+    # type: (str) -> HiddenText
+    return HiddenText(value, redacted='****')
+
+
+def hide_url(url):
+    # type: (str) -> HiddenText
+    redacted = redact_auth_from_url(url)
+    return HiddenText(url, redacted=redacted)
+
+
+def protect_pip_from_modification_on_windows(modifying_pip):
+    # type: (bool) -> None
+    """Protection of pip.exe from modification on Windows
+
+    On Windows, any operation modifying pip should be run as:
+        python -m pip ...
+    """
+    pip_names = [
+        "pip.exe",
+        "pip{}.exe".format(sys.version_info[0]),
+        "pip{}.{}.exe".format(*sys.version_info[:2])
+    ]
+
+    # See https://github.com/pypa/pip/issues/1299 for more discussion
+    should_show_use_python_msg = (
+        modifying_pip and
+        WINDOWS and
+        os.path.basename(sys.argv[0]) in pip_names
+    )
+
+    if should_show_use_python_msg:
+        new_command = [
+            sys.executable, "-m", "pip"
+        ] + sys.argv[1:]
+        raise CommandError(
+            'To modify pip, please run the following command:\n{}'
+            .format(" ".join(new_command))
+        )
+
+
+def is_console_interactive():
+    # type: () -> bool
+    """Is this console interactive?
+    """
+    return sys.stdin is not None and sys.stdin.isatty()
+
+
+def hash_file(path, blocksize=1 << 20):
+    # type: (str, int) -> Tuple[Any, int]
+    """Return (hash, length) for path using hashlib.sha256()
+    """
+
+    h = hashlib.sha256()
+    length = 0
+    with open(path, 'rb') as f:
+        for block in read_chunks(f, size=blocksize):
+            length += len(block)
+            h.update(block)
+    return h, length
+
+
+def is_wheel_installed():
+    """
+    Return whether the wheel package is installed.
+    """
+    try:
+        import wheel  # noqa: F401
+    except ImportError:
+        return False
+
+    return True

env/lib/python3.8/site-packages/pip/_internal/utils/models.py

@@ -0,0 +1,42 @@
+"""Utilities for defining models
+"""
+# The following comment should be removed at some point in the future.
+# mypy: disallow-untyped-defs=False
+
+import operator
+
+
+class KeyBasedCompareMixin(object):
+    """Provides comparison capabilities that is based on a key
+    """
+
+    def __init__(self, key, defining_class):
+        self._compare_key = key
+        self._defining_class = defining_class
+
+    def __hash__(self):
+        return hash(self._compare_key)
+
+    def __lt__(self, other):
+        return self._compare(other, operator.__lt__)
+
+    def __le__(self, other):
+        return self._compare(other, operator.__le__)
+
+    def __gt__(self, other):
+        return self._compare(other, operator.__gt__)
+
+    def __ge__(self, other):
+        return self._compare(other, operator.__ge__)
+
+    def __eq__(self, other):
+        return self._compare(other, operator.__eq__)
+
+    def __ne__(self, other):
+        return self._compare(other, operator.__ne__)
+
+    def _compare(self, other, method):
+        if not isinstance(other, self._defining_class):
+            return NotImplemented
+
+        return method(self._compare_key, other._compare_key)

env/lib/python3.8/site-packages/pip/_internal/utils/packaging.py

@@ -0,0 +1,94 @@
+from __future__ import absolute_import
+
+import logging
+from email.parser import FeedParser
+
+from pip._vendor import pkg_resources
+from pip._vendor.packaging import specifiers, version
+
+from pip._internal.exceptions import NoneMetadataError
+from pip._internal.utils.misc import display_path
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Optional, Tuple
+    from email.message import Message
+    from pip._vendor.pkg_resources import Distribution
+
+
+logger = logging.getLogger(__name__)
+
+
+def check_requires_python(requires_python, version_info):
+    # type: (Optional[str], Tuple[int, ...]) -> bool
+    """
+    Check if the given Python version matches a "Requires-Python" specifier.
+
+    :param version_info: A 3-tuple of ints representing a Python
+        major-minor-micro version to check (e.g. `sys.version_info[:3]`).
+
+    :return: `True` if the given Python version satisfies the requirement.
+        Otherwise, return `False`.
+
+    :raises InvalidSpecifier: If `requires_python` has an invalid format.
+    """
+    if requires_python is None:
+        # The package provides no information
+        return True
+    requires_python_specifier = specifiers.SpecifierSet(requires_python)
+
+    python_version = version.parse('.'.join(map(str, version_info)))
+    return python_version in requires_python_specifier
+
+
+def get_metadata(dist):
+    # type: (Distribution) -> Message
+    """
+    :raises NoneMetadataError: if the distribution reports `has_metadata()`
+        True but `get_metadata()` returns None.
+    """
+    metadata_name = 'METADATA'
+    if (isinstance(dist, pkg_resources.DistInfoDistribution) and
+            dist.has_metadata(metadata_name)):
+        metadata = dist.get_metadata(metadata_name)
+    elif dist.has_metadata('PKG-INFO'):
+        metadata_name = 'PKG-INFO'
+        metadata = dist.get_metadata(metadata_name)
+    else:
+        logger.warning("No metadata found in %s", display_path(dist.location))
+        metadata = ''
+
+    if metadata is None:
+        raise NoneMetadataError(dist, metadata_name)
+
+    feed_parser = FeedParser()
+    # The following line errors out if with a "NoneType" TypeError if
+    # passed metadata=None.
+    feed_parser.feed(metadata)
+    return feed_parser.close()
+
+
+def get_requires_python(dist):
+    # type: (pkg_resources.Distribution) -> Optional[str]
+    """
+    Return the "Requires-Python" metadata for a distribution, or None
+    if not present.
+    """
+    pkg_info_dict = get_metadata(dist)
+    requires_python = pkg_info_dict.get('Requires-Python')
+
+    if requires_python is not None:
+        # Convert to a str to satisfy the type checker, since requires_python
+        # can be a Header object.
+        requires_python = str(requires_python)
+
+    return requires_python
+
+
+def get_installer(dist):
+    # type: (Distribution) -> str
+    if dist.has_metadata('INSTALLER'):
+        for line in dist.get_metadata_lines('INSTALLER'):
+            if line.strip():
+                return line.strip()
+    return ''

env/lib/python3.8/site-packages/pip/_internal/utils/pkg_resources.py

@@ -0,0 +1,44 @@
+from pip._vendor.pkg_resources import yield_lines
+from pip._vendor.six import ensure_str
+
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Dict, Iterable, List
+
+
+class DictMetadata(object):
+    """IMetadataProvider that reads metadata files from a dictionary.
+    """
+    def __init__(self, metadata):
+        # type: (Dict[str, bytes]) -> None
+        self._metadata = metadata
+
+    def has_metadata(self, name):
+        # type: (str) -> bool
+        return name in self._metadata
+
+    def get_metadata(self, name):
+        # type: (str) -> str
+        try:
+            return ensure_str(self._metadata[name])
+        except UnicodeDecodeError as e:
+            # Mirrors handling done in pkg_resources.NullProvider.
+            e.reason += " in {} file".format(name)
+            raise
+
+    def get_metadata_lines(self, name):
+        # type: (str) -> Iterable[str]
+        return yield_lines(self.get_metadata(name))
+
+    def metadata_isdir(self, name):
+        # type: (str) -> bool
+        return False
+
+    def metadata_listdir(self, name):
+        # type: (str) -> List[str]
+        return []
+
+    def run_script(self, script_name, namespace):
+        # type: (str, str) -> None
+        pass

env/lib/python3.8/site-packages/pip/_internal/utils/setuptools_build.py

@@ -0,0 +1,181 @@
+import sys
+
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import List, Optional, Sequence
+
+# Shim to wrap setup.py invocation with setuptools
+#
+# We set sys.argv[0] to the path to the underlying setup.py file so
+# setuptools / distutils don't take the path to the setup.py to be "-c" when
+# invoking via the shim.  This avoids e.g. the following manifest_maker
+# warning: "warning: manifest_maker: standard file '-c' not found".
+_SETUPTOOLS_SHIM = (
+    "import sys, setuptools, tokenize; sys.argv[0] = {0!r}; __file__={0!r};"
+    "f=getattr(tokenize, 'open', open)(__file__);"
+    "code=f.read().replace('\\r\\n', '\\n');"
+    "f.close();"
+    "exec(compile(code, __file__, 'exec'))"
+)
+
+
+def make_setuptools_shim_args(
+    setup_py_path,  # type: str
+    global_options=None,  # type: Sequence[str]
+    no_user_config=False,  # type: bool
+    unbuffered_output=False  # type: bool
+):
+    # type: (...) -> List[str]
+    """
+    Get setuptools command arguments with shim wrapped setup file invocation.
+
+    :param setup_py_path: The path to setup.py to be wrapped.
+    :param global_options: Additional global options.
+    :param no_user_config: If True, disables personal user configuration.
+    :param unbuffered_output: If True, adds the unbuffered switch to the
+     argument list.
+    """
+    args = [sys.executable]
+    if unbuffered_output:
+        args += ["-u"]
+    args += ["-c", _SETUPTOOLS_SHIM.format(setup_py_path)]
+    if global_options:
+        args += global_options
+    if no_user_config:
+        args += ["--no-user-cfg"]
+    return args
+
+
+def make_setuptools_bdist_wheel_args(
+    setup_py_path,  # type: str
+    global_options,  # type: Sequence[str]
+    build_options,  # type: Sequence[str]
+    destination_dir,  # type: str
+):
+    # type: (...) -> List[str]
+    # NOTE: Eventually, we'd want to also -S to the flags here, when we're
+    # isolating. Currently, it breaks Python in virtualenvs, because it
+    # relies on site.py to find parts of the standard library outside the
+    # virtualenv.
+    args = make_setuptools_shim_args(
+        setup_py_path,
+        global_options=global_options,
+        unbuffered_output=True
+    )
+    args += ["bdist_wheel", "-d", destination_dir]
+    args += build_options
+    return args
+
+
+def make_setuptools_clean_args(
+    setup_py_path,  # type: str
+    global_options,  # type: Sequence[str]
+):
+    # type: (...) -> List[str]
+    args = make_setuptools_shim_args(
+        setup_py_path,
+        global_options=global_options,
+        unbuffered_output=True
+    )
+    args += ["clean", "--all"]
+    return args
+
+
+def make_setuptools_develop_args(
+    setup_py_path,  # type: str
+    global_options,  # type: Sequence[str]
+    install_options,  # type: Sequence[str]
+    no_user_config,  # type: bool
+    prefix,  # type: Optional[str]
+    home,  # type: Optional[str]
+    use_user_site,  # type: bool
+):
+    # type: (...) -> List[str]
+    assert not (use_user_site and prefix)
+
+    args = make_setuptools_shim_args(
+        setup_py_path,
+        global_options=global_options,
+        no_user_config=no_user_config,
+    )
+
+    args += ["develop", "--no-deps"]
+
+    args += install_options
+
+    if prefix:
+        args += ["--prefix", prefix]
+    if home is not None:
+        args += ["--home", home]
+
+    if use_user_site:
+        args += ["--user", "--prefix="]
+
+    return args
+
+
+def make_setuptools_egg_info_args(
+    setup_py_path,  # type: str
+    egg_info_dir,  # type: Optional[str]
+    no_user_config,  # type: bool
+):
+    # type: (...) -> List[str]
+    args = make_setuptools_shim_args(setup_py_path)
+    if no_user_config:
+        args += ["--no-user-cfg"]
+
+    args += ["egg_info"]
+
+    if egg_info_dir:
+        args += ["--egg-base", egg_info_dir]
+
+    return args
+
+
+def make_setuptools_install_args(
+    setup_py_path,  # type: str
+    global_options,  # type: Sequence[str]
+    install_options,  # type: Sequence[str]
+    record_filename,  # type: str
+    root,  # type: Optional[str]
+    prefix,  # type: Optional[str]
+    header_dir,  # type: Optional[str]
+    home,  # type: Optional[str]
+    use_user_site,  # type: bool
+    no_user_config,  # type: bool
+    pycompile  # type: bool
+):
+    # type: (...) -> List[str]
+    assert not (use_user_site and prefix)
+    assert not (use_user_site and root)
+
+    args = make_setuptools_shim_args(
+        setup_py_path,
+        global_options=global_options,
+        no_user_config=no_user_config,
+        unbuffered_output=True
+    )
+    args += ["install", "--record", record_filename]
+    args += ["--single-version-externally-managed"]
+
+    if root is not None:
+        args += ["--root", root]
+    if prefix is not None:
+        args += ["--prefix", prefix]
+    if home is not None:
+        args += ["--home", home]
+    if use_user_site:
+        args += ["--user", "--prefix="]
+
+    if pycompile:
+        args += ["--compile"]
+    else:
+        args += ["--no-compile"]
+
+    if header_dir:
+        args += ["--install-headers", header_dir]
+
+    args += install_options
+
+    return args

env/lib/python3.8/site-packages/pip/_internal/utils/subprocess.py

@@ -0,0 +1,278 @@
+# The following comment should be removed at some point in the future.
+# mypy: strict-optional=False
+
+from __future__ import absolute_import
+
+import logging
+import os
+import subprocess
+
+from pip._vendor.six.moves import shlex_quote
+
+from pip._internal.exceptions import InstallationError
+from pip._internal.utils.compat import console_to_str, str_to_display
+from pip._internal.utils.logging import subprocess_logger
+from pip._internal.utils.misc import HiddenText, path_to_display
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+from pip._internal.utils.ui import open_spinner
+
+if MYPY_CHECK_RUNNING:
+    from typing import (
+        Any, Callable, Iterable, List, Mapping, Optional, Text, Union,
+    )
+    from pip._internal.utils.ui import SpinnerInterface
+
+    CommandArgs = List[Union[str, HiddenText]]
+
+
+LOG_DIVIDER = '----------------------------------------'
+
+
+def make_command(*args):
+    # type: (Union[str, HiddenText, CommandArgs]) -> CommandArgs
+    """
+    Create a CommandArgs object.
+    """
+    command_args = []  # type: CommandArgs
+    for arg in args:
+        # Check for list instead of CommandArgs since CommandArgs is
+        # only known during type-checking.
+        if isinstance(arg, list):
+            command_args.extend(arg)
+        else:
+            # Otherwise, arg is str or HiddenText.
+            command_args.append(arg)
+
+    return command_args
+
+
+def format_command_args(args):
+    # type: (Union[List[str], CommandArgs]) -> str
+    """
+    Format command arguments for display.
+    """
+    # For HiddenText arguments, display the redacted form by calling str().
+    # Also, we don't apply str() to arguments that aren't HiddenText since
+    # this can trigger a UnicodeDecodeError in Python 2 if the argument
+    # has type unicode and includes a non-ascii character.  (The type
+    # checker doesn't ensure the annotations are correct in all cases.)
+    return ' '.join(
+        shlex_quote(str(arg)) if isinstance(arg, HiddenText)
+        else shlex_quote(arg) for arg in args
+    )
+
+
+def reveal_command_args(args):
+    # type: (Union[List[str], CommandArgs]) -> List[str]
+    """
+    Return the arguments in their raw, unredacted form.
+    """
+    return [
+        arg.secret if isinstance(arg, HiddenText) else arg for arg in args
+    ]
+
+
+def make_subprocess_output_error(
+    cmd_args,     # type: Union[List[str], CommandArgs]
+    cwd,          # type: Optional[str]
+    lines,        # type: List[Text]
+    exit_status,  # type: int
+):
+    # type: (...) -> Text
+    """
+    Create and return the error message to use to log a subprocess error
+    with command output.
+
+    :param lines: A list of lines, each ending with a newline.
+    """
+    command = format_command_args(cmd_args)
+    # Convert `command` and `cwd` to text (unicode in Python 2) so we can use
+    # them as arguments in the unicode format string below. This avoids
+    # "UnicodeDecodeError: 'ascii' codec can't decode byte ..." in Python 2
+    # if either contains a non-ascii character.
+    command_display = str_to_display(command, desc='command bytes')
+    cwd_display = path_to_display(cwd)
+
+    # We know the joined output value ends in a newline.
+    output = ''.join(lines)
+    msg = (
+        # Use a unicode string to avoid "UnicodeEncodeError: 'ascii'
+        # codec can't encode character ..." in Python 2 when a format
+        # argument (e.g. `output`) has a non-ascii character.
+        u'Command errored out with exit status {exit_status}:\n'
+        ' command: {command_display}\n'
+        '     cwd: {cwd_display}\n'
+        'Complete output ({line_count} lines):\n{output}{divider}'
+    ).format(
+        exit_status=exit_status,
+        command_display=command_display,
+        cwd_display=cwd_display,
+        line_count=len(lines),
+        output=output,
+        divider=LOG_DIVIDER,
+    )
+    return msg
+
+
+def call_subprocess(
+    cmd,  # type: Union[List[str], CommandArgs]
+    show_stdout=False,  # type: bool
+    cwd=None,  # type: Optional[str]
+    on_returncode='raise',  # type: str
+    extra_ok_returncodes=None,  # type: Optional[Iterable[int]]
+    command_desc=None,  # type: Optional[str]
+    extra_environ=None,  # type: Optional[Mapping[str, Any]]
+    unset_environ=None,  # type: Optional[Iterable[str]]
+    spinner=None,  # type: Optional[SpinnerInterface]
+    log_failed_cmd=True  # type: Optional[bool]
+):
+    # type: (...) -> Text
+    """
+    Args:
+      show_stdout: if true, use INFO to log the subprocess's stderr and
+        stdout streams.  Otherwise, use DEBUG.  Defaults to False.
+      extra_ok_returncodes: an iterable of integer return codes that are
+        acceptable, in addition to 0. Defaults to None, which means [].
+      unset_environ: an iterable of environment variable names to unset
+        prior to calling subprocess.Popen().
+      log_failed_cmd: if false, failed commands are not logged, only raised.
+    """
+    if extra_ok_returncodes is None:
+        extra_ok_returncodes = []
+    if unset_environ is None:
+        unset_environ = []
+    # Most places in pip use show_stdout=False. What this means is--
+    #
+    # - We connect the child's output (combined stderr and stdout) to a
+    #   single pipe, which we read.
+    # - We log this output to stderr at DEBUG level as it is received.
+    # - If DEBUG logging isn't enabled (e.g. if --verbose logging wasn't
+    #   requested), then we show a spinner so the user can still see the
+    #   subprocess is in progress.
+    # - If the subprocess exits with an error, we log the output to stderr
+    #   at ERROR level if it hasn't already been displayed to the console
+    #   (e.g. if --verbose logging wasn't enabled).  This way we don't log
+    #   the output to the console twice.
+    #
+    # If show_stdout=True, then the above is still done, but with DEBUG
+    # replaced by INFO.
+    if show_stdout:
+        # Then log the subprocess output at INFO level.
+        log_subprocess = subprocess_logger.info
+        used_level = logging.INFO
+    else:
+        # Then log the subprocess output using DEBUG.  This also ensures
+        # it will be logged to the log file (aka user_log), if enabled.
+        log_subprocess = subprocess_logger.debug
+        used_level = logging.DEBUG
+
+    # Whether the subprocess will be visible in the console.
+    showing_subprocess = subprocess_logger.getEffectiveLevel() <= used_level
+
+    # Only use the spinner if we're not showing the subprocess output
+    # and we have a spinner.
+    use_spinner = not showing_subprocess and spinner is not None
+
+    if command_desc is None:
+        command_desc = format_command_args(cmd)
+
+    log_subprocess("Running command %s", command_desc)
+    env = os.environ.copy()
+    if extra_environ:
+        env.update(extra_environ)
+    for name in unset_environ:
+        env.pop(name, None)
+    try:
+        proc = subprocess.Popen(
+            # Convert HiddenText objects to the underlying str.
+            reveal_command_args(cmd),
+            stderr=subprocess.STDOUT, stdin=subprocess.PIPE,
+            stdout=subprocess.PIPE, cwd=cwd, env=env,
+        )
+        proc.stdin.close()
+    except Exception as exc:
+        if log_failed_cmd:
+            subprocess_logger.critical(
+                "Error %s while executing command %s", exc, command_desc,
+            )
+        raise
+    all_output = []
+    while True:
+        # The "line" value is a unicode string in Python 2.
+        line = console_to_str(proc.stdout.readline())
+        if not line:
+            break
+        line = line.rstrip()
+        all_output.append(line + '\n')
+
+        # Show the line immediately.
+        log_subprocess(line)
+        # Update the spinner.
+        if use_spinner:
+            spinner.spin()
+    try:
+        proc.wait()
+    finally:
+        if proc.stdout:
+            proc.stdout.close()
+    proc_had_error = (
+        proc.returncode and proc.returncode not in extra_ok_returncodes
+    )
+    if use_spinner:
+        if proc_had_error:
+            spinner.finish("error")
+        else:
+            spinner.finish("done")
+    if proc_had_error:
+        if on_returncode == 'raise':
+            if not showing_subprocess and log_failed_cmd:
+                # Then the subprocess streams haven't been logged to the
+                # console yet.
+                msg = make_subprocess_output_error(
+                    cmd_args=cmd,
+                    cwd=cwd,
+                    lines=all_output,
+                    exit_status=proc.returncode,
+                )
+                subprocess_logger.error(msg)
+            exc_msg = (
+                'Command errored out with exit status {}: {} '
+                'Check the logs for full command output.'
+            ).format(proc.returncode, command_desc)
+            raise InstallationError(exc_msg)
+        elif on_returncode == 'warn':
+            subprocess_logger.warning(
+                'Command "%s" had error code %s in %s',
+                command_desc, proc.returncode, cwd,
+            )
+        elif on_returncode == 'ignore':
+            pass
+        else:
+            raise ValueError('Invalid value: on_returncode=%s' %
+                             repr(on_returncode))
+    return ''.join(all_output)
+
+
+def runner_with_spinner_message(message):
+    # type: (str) -> Callable[..., None]
+    """Provide a subprocess_runner that shows a spinner message.
+
+    Intended for use with for pep517's Pep517HookCaller. Thus, the runner has
+    an API that matches what's expected by Pep517HookCaller.subprocess_runner.
+    """
+
+    def runner(
+        cmd,  # type: List[str]
+        cwd=None,  # type: Optional[str]
+        extra_environ=None  # type: Optional[Mapping[str, Any]]
+    ):
+        # type: (...) -> None
+        with open_spinner(message) as spinner:
+            call_subprocess(
+                cmd,
+                cwd=cwd,
+                extra_environ=extra_environ,
+                spinner=spinner,
+            )
+
+    return runner

env/lib/python3.8/site-packages/pip/_internal/utils/temp_dir.py

@@ -0,0 +1,250 @@
+from __future__ import absolute_import
+
+import errno
+import itertools
+import logging
+import os.path
+import tempfile
+from contextlib import contextmanager
+
+from pip._vendor.contextlib2 import ExitStack
+
+from pip._internal.utils.misc import rmtree
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Any, Dict, Iterator, Optional, TypeVar
+
+    _T = TypeVar('_T', bound='TempDirectory')
+
+
+logger = logging.getLogger(__name__)
+
+
+_tempdir_manager = None  # type: Optional[ExitStack]
+
+
+@contextmanager
+def global_tempdir_manager():
+    # type: () -> Iterator[None]
+    global _tempdir_manager
+    with ExitStack() as stack:
+        old_tempdir_manager, _tempdir_manager = _tempdir_manager, stack
+        try:
+            yield
+        finally:
+            _tempdir_manager = old_tempdir_manager
+
+
+class TempDirectoryTypeRegistry(object):
+    """Manages temp directory behavior
+    """
+
+    def __init__(self):
+        # type: () -> None
+        self._should_delete = {}  # type: Dict[str, bool]
+
+    def set_delete(self, kind, value):
+        # type: (str, bool) -> None
+        """Indicate whether a TempDirectory of the given kind should be
+        auto-deleted.
+        """
+        self._should_delete[kind] = value
+
+    def get_delete(self, kind):
+        # type: (str) -> bool
+        """Get configured auto-delete flag for a given TempDirectory type,
+        default True.
+        """
+        return self._should_delete.get(kind, True)
+
+
+_tempdir_registry = None  # type: Optional[TempDirectoryTypeRegistry]
+
+
+@contextmanager
+def tempdir_registry():
+    # type: () -> Iterator[TempDirectoryTypeRegistry]
+    """Provides a scoped global tempdir registry that can be used to dictate
+    whether directories should be deleted.
+    """
+    global _tempdir_registry
+    old_tempdir_registry = _tempdir_registry
+    _tempdir_registry = TempDirectoryTypeRegistry()
+    try:
+        yield _tempdir_registry
+    finally:
+        _tempdir_registry = old_tempdir_registry
+
+
+class TempDirectory(object):
+    """Helper class that owns and cleans up a temporary directory.
+
+    This class can be used as a context manager or as an OO representation of a
+    temporary directory.
+
+    Attributes:
+        path
+            Location to the created temporary directory
+        delete
+            Whether the directory should be deleted when exiting
+            (when used as a contextmanager)
+
+    Methods:
+        cleanup()
+            Deletes the temporary directory
+
+    When used as a context manager, if the delete attribute is True, on
+    exiting the context the temporary directory is deleted.
+    """
+
+    def __init__(
+        self,
+        path=None,    # type: Optional[str]
+        delete=None,  # type: Optional[bool]
+        kind="temp",  # type: str
+        globally_managed=False,  # type: bool
+    ):
+        super(TempDirectory, self).__init__()
+
+        # If we were given an explicit directory, resolve delete option now.
+        # Otherwise we wait until cleanup and see what tempdir_registry says.
+        if path is not None and delete is None:
+            delete = False
+
+        if path is None:
+            path = self._create(kind)
+
+        self._path = path
+        self._deleted = False
+        self.delete = delete
+        self.kind = kind
+
+        if globally_managed:
+            assert _tempdir_manager is not None
+            _tempdir_manager.enter_context(self)
+
+    @property
+    def path(self):
+        # type: () -> str
+        assert not self._deleted, (
+            "Attempted to access deleted path: {}".format(self._path)
+        )
+        return self._path
+
+    def __repr__(self):
+        # type: () -> str
+        return "<{} {!r}>".format(self.__class__.__name__, self.path)
+
+    def __enter__(self):
+        # type: (_T) -> _T
+        return self
+
+    def __exit__(self, exc, value, tb):
+        # type: (Any, Any, Any) -> None
+        if self.delete is not None:
+            delete = self.delete
+        elif _tempdir_registry:
+            delete = _tempdir_registry.get_delete(self.kind)
+        else:
+            delete = True
+
+        if delete:
+            self.cleanup()
+
+    def _create(self, kind):
+        # type: (str) -> str
+        """Create a temporary directory and store its path in self.path
+        """
+        # We realpath here because some systems have their default tmpdir
+        # symlinked to another directory.  This tends to confuse build
+        # scripts, so we canonicalize the path by traversing potential
+        # symlinks here.
+        path = os.path.realpath(
+            tempfile.mkdtemp(prefix="pip-{}-".format(kind))
+        )
+        logger.debug("Created temporary directory: {}".format(path))
+        return path
+
+    def cleanup(self):
+        # type: () -> None
+        """Remove the temporary directory created and reset state
+        """
+        self._deleted = True
+        if os.path.exists(self._path):
+            rmtree(self._path)
+
+
+class AdjacentTempDirectory(TempDirectory):
+    """Helper class that creates a temporary directory adjacent to a real one.
+
+    Attributes:
+        original
+            The original directory to create a temp directory for.
+        path
+            After calling create() or entering, contains the full
+            path to the temporary directory.
+        delete
+            Whether the directory should be deleted when exiting
+            (when used as a contextmanager)
+
+    """
+    # The characters that may be used to name the temp directory
+    # We always prepend a ~ and then rotate through these until
+    # a usable name is found.
+    # pkg_resources raises a different error for .dist-info folder
+    # with leading '-' and invalid metadata
+    LEADING_CHARS = "-~.=%0123456789"
+
+    def __init__(self, original, delete=None):
+        # type: (str, Optional[bool]) -> None
+        self.original = original.rstrip('/\\')
+        super(AdjacentTempDirectory, self).__init__(delete=delete)
+
+    @classmethod
+    def _generate_names(cls, name):
+        # type: (str) -> Iterator[str]
+        """Generates a series of temporary names.
+
+        The algorithm replaces the leading characters in the name
+        with ones that are valid filesystem characters, but are not
+        valid package names (for both Python and pip definitions of
+        package).
+        """
+        for i in range(1, len(name)):
+            for candidate in itertools.combinations_with_replacement(
+                    cls.LEADING_CHARS, i - 1):
+                new_name = '~' + ''.join(candidate) + name[i:]
+                if new_name != name:
+                    yield new_name
+
+        # If we make it this far, we will have to make a longer name
+        for i in range(len(cls.LEADING_CHARS)):
+            for candidate in itertools.combinations_with_replacement(
+                    cls.LEADING_CHARS, i):
+                new_name = '~' + ''.join(candidate) + name
+                if new_name != name:
+                    yield new_name
+
+    def _create(self, kind):
+        # type: (str) -> str
+        root, name = os.path.split(self.original)
+        for candidate in self._generate_names(name):
+            path = os.path.join(root, candidate)
+            try:
+                os.mkdir(path)
+            except OSError as ex:
+                # Continue if the name exists already
+                if ex.errno != errno.EEXIST:
+                    raise
+            else:
+                path = os.path.realpath(path)
+                break
+        else:
+            # Final fallback on the default behavior.
+            path = os.path.realpath(
+                tempfile.mkdtemp(prefix="pip-{}-".format(kind))
+            )
+
+        logger.debug("Created temporary directory: {}".format(path))
+        return path

env/lib/python3.8/site-packages/pip/_internal/utils/typing.py

@@ -0,0 +1,38 @@
+"""For neatly implementing static typing in pip.
+
+`mypy` - the static type analysis tool we use - uses the `typing` module, which
+provides core functionality fundamental to mypy's functioning.
+
+Generally, `typing` would be imported at runtime and used in that fashion -
+it acts as a no-op at runtime and does not have any run-time overhead by
+design.
+
+As it turns out, `typing` is not vendorable - it uses separate sources for
+Python 2/Python 3. Thus, this codebase can not expect it to be present.
+To work around this, mypy allows the typing import to be behind a False-y
+optional to prevent it from running at runtime and type-comments can be used
+to remove the need for the types to be accessible directly during runtime.
+
+This module provides the False-y guard in a nicely named fashion so that a
+curious maintainer can reach here to read this.
+
+In pip, all static-typing related imports should be guarded as follows:
+
+    from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+    if MYPY_CHECK_RUNNING:
+        from typing import ...
+
+Ref: https://github.com/python/mypy/issues/3216
+"""
+
+MYPY_CHECK_RUNNING = False
+
+
+if MYPY_CHECK_RUNNING:
+    from typing import cast
+else:
+    # typing's cast() is needed at runtime, but we don't want to import typing.
+    # Thus, we use a dummy no-op version, which we tell mypy to ignore.
+    def cast(type_, value):  # type: ignore
+        return value

env/lib/python3.8/site-packages/pip/_internal/utils/ui.py

@@ -0,0 +1,428 @@
+# The following comment should be removed at some point in the future.
+# mypy: strict-optional=False
+# mypy: disallow-untyped-defs=False
+
+from __future__ import absolute_import, division
+
+import contextlib
+import itertools
+import logging
+import sys
+import time
+from signal import SIGINT, default_int_handler, signal
+
+from pip._vendor import six
+from pip._vendor.progress import HIDE_CURSOR, SHOW_CURSOR
+from pip._vendor.progress.bar import Bar, FillingCirclesBar, IncrementalBar
+from pip._vendor.progress.spinner import Spinner
+
+from pip._internal.utils.compat import WINDOWS
+from pip._internal.utils.logging import get_indentation
+from pip._internal.utils.misc import format_size
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Any, Iterator, IO
+
+try:
+    from pip._vendor import colorama
+# Lots of different errors can come from this, including SystemError and
+# ImportError.
+except Exception:
+    colorama = None
+
+logger = logging.getLogger(__name__)
+
+
+def _select_progress_class(preferred, fallback):
+    encoding = getattr(preferred.file, "encoding", None)
+
+    # If we don't know what encoding this file is in, then we'll just assume
+    # that it doesn't support unicode and use the ASCII bar.
+    if not encoding:
+        return fallback
+
+    # Collect all of the possible characters we want to use with the preferred
+    # bar.
+    characters = [
+        getattr(preferred, "empty_fill", six.text_type()),
+        getattr(preferred, "fill", six.text_type()),
+    ]
+    characters += list(getattr(preferred, "phases", []))
+
+    # Try to decode the characters we're using for the bar using the encoding
+    # of the given file, if this works then we'll assume that we can use the
+    # fancier bar and if not we'll fall back to the plaintext bar.
+    try:
+        six.text_type().join(characters).encode(encoding)
+    except UnicodeEncodeError:
+        return fallback
+    else:
+        return preferred
+
+
+_BaseBar = _select_progress_class(IncrementalBar, Bar)  # type: Any
+
+
+class InterruptibleMixin(object):
+    """
+    Helper to ensure that self.finish() gets called on keyboard interrupt.
+
+    This allows downloads to be interrupted without leaving temporary state
+    (like hidden cursors) behind.
+
+    This class is similar to the progress library's existing SigIntMixin
+    helper, but as of version 1.2, that helper has the following problems:
+
+    1. It calls sys.exit().
+    2. It discards the existing SIGINT handler completely.
+    3. It leaves its own handler in place even after an uninterrupted finish,
+       which will have unexpected delayed effects if the user triggers an
+       unrelated keyboard interrupt some time after a progress-displaying
+       download has already completed, for example.
+    """
+
+    def __init__(self, *args, **kwargs):
+        """
+        Save the original SIGINT handler for later.
+        """
+        super(InterruptibleMixin, self).__init__(*args, **kwargs)
+
+        self.original_handler = signal(SIGINT, self.handle_sigint)
+
+        # If signal() returns None, the previous handler was not installed from
+        # Python, and we cannot restore it. This probably should not happen,
+        # but if it does, we must restore something sensible instead, at least.
+        # The least bad option should be Python's default SIGINT handler, which
+        # just raises KeyboardInterrupt.
+        if self.original_handler is None:
+            self.original_handler = default_int_handler
+
+    def finish(self):
+        """
+        Restore the original SIGINT handler after finishing.
+
+        This should happen regardless of whether the progress display finishes
+        normally, or gets interrupted.
+        """
+        super(InterruptibleMixin, self).finish()
+        signal(SIGINT, self.original_handler)
+
+    def handle_sigint(self, signum, frame):
+        """
+        Call self.finish() before delegating to the original SIGINT handler.
+
+        This handler should only be in place while the progress display is
+        active.
+        """
+        self.finish()
+        self.original_handler(signum, frame)
+
+
+class SilentBar(Bar):
+
+    def update(self):
+        pass
+
+
+class BlueEmojiBar(IncrementalBar):
+
+    suffix = "%(percent)d%%"
+    bar_prefix = " "
+    bar_suffix = " "
+    phases = (u"\U0001F539", u"\U0001F537", u"\U0001F535")  # type: Any
+
+
+class DownloadProgressMixin(object):
+
+    def __init__(self, *args, **kwargs):
+        super(DownloadProgressMixin, self).__init__(*args, **kwargs)
+        self.message = (" " * (get_indentation() + 2)) + self.message
+
+    @property
+    def downloaded(self):
+        return format_size(self.index)
+
+    @property
+    def download_speed(self):
+        # Avoid zero division errors...
+        if self.avg == 0.0:
+            return "..."
+        return format_size(1 / self.avg) + "/s"
+
+    @property
+    def pretty_eta(self):
+        if self.eta:
+            return "eta %s" % self.eta_td
+        return ""
+
+    def iter(self, it):
+        for x in it:
+            yield x
+            self.next(len(x))
+        self.finish()
+
+
+class WindowsMixin(object):
+
+    def __init__(self, *args, **kwargs):
+        # The Windows terminal does not support the hide/show cursor ANSI codes
+        # even with colorama. So we'll ensure that hide_cursor is False on
+        # Windows.
+        # This call needs to go before the super() call, so that hide_cursor
+        # is set in time. The base progress bar class writes the "hide cursor"
+        # code to the terminal in its init, so if we don't set this soon
+        # enough, we get a "hide" with no corresponding "show"...
+        if WINDOWS and self.hide_cursor:
+            self.hide_cursor = False
+
+        super(WindowsMixin, self).__init__(*args, **kwargs)
+
+        # Check if we are running on Windows and we have the colorama module,
+        # if we do then wrap our file with it.
+        if WINDOWS and colorama:
+            self.file = colorama.AnsiToWin32(self.file)
+            # The progress code expects to be able to call self.file.isatty()
+            # but the colorama.AnsiToWin32() object doesn't have that, so we'll
+            # add it.
+            self.file.isatty = lambda: self.file.wrapped.isatty()
+            # The progress code expects to be able to call self.file.flush()
+            # but the colorama.AnsiToWin32() object doesn't have that, so we'll
+            # add it.
+            self.file.flush = lambda: self.file.wrapped.flush()
+
+
+class BaseDownloadProgressBar(WindowsMixin, InterruptibleMixin,
+                              DownloadProgressMixin):
+
+    file = sys.stdout
+    message = "%(percent)d%%"
+    suffix = "%(downloaded)s %(download_speed)s %(pretty_eta)s"
+
+# NOTE: The "type: ignore" comments on the following classes are there to
+#       work around https://github.com/python/typing/issues/241
+
+
+class DefaultDownloadProgressBar(BaseDownloadProgressBar,
+                                 _BaseBar):
+    pass
+
+
+class DownloadSilentBar(BaseDownloadProgressBar, SilentBar):  # type: ignore
+    pass
+
+
+class DownloadBar(BaseDownloadProgressBar,  # type: ignore
+                  Bar):
+    pass
+
+
+class DownloadFillingCirclesBar(BaseDownloadProgressBar,  # type: ignore
+                                FillingCirclesBar):
+    pass
+
+
+class DownloadBlueEmojiProgressBar(BaseDownloadProgressBar,  # type: ignore
+                                   BlueEmojiBar):
+    pass
+
+
+class DownloadProgressSpinner(WindowsMixin, InterruptibleMixin,
+                              DownloadProgressMixin, Spinner):
+
+    file = sys.stdout
+    suffix = "%(downloaded)s %(download_speed)s"
+
+    def next_phase(self):
+        if not hasattr(self, "_phaser"):
+            self._phaser = itertools.cycle(self.phases)
+        return next(self._phaser)
+
+    def update(self):
+        message = self.message % self
+        phase = self.next_phase()
+        suffix = self.suffix % self
+        line = ''.join([
+            message,
+            " " if message else "",
+            phase,
+            " " if suffix else "",
+            suffix,
+        ])
+
+        self.writeln(line)
+
+
+BAR_TYPES = {
+    "off": (DownloadSilentBar, DownloadSilentBar),
+    "on": (DefaultDownloadProgressBar, DownloadProgressSpinner),
+    "ascii": (DownloadBar, DownloadProgressSpinner),
+    "pretty": (DownloadFillingCirclesBar, DownloadProgressSpinner),
+    "emoji": (DownloadBlueEmojiProgressBar, DownloadProgressSpinner)
+}
+
+
+def DownloadProgressProvider(progress_bar, max=None):
+    if max is None or max == 0:
+        return BAR_TYPES[progress_bar][1]().iter
+    else:
+        return BAR_TYPES[progress_bar][0](max=max).iter
+
+
+################################################################
+# Generic "something is happening" spinners
+#
+# We don't even try using progress.spinner.Spinner here because it's actually
+# simpler to reimplement from scratch than to coerce their code into doing
+# what we need.
+################################################################
+
+@contextlib.contextmanager
+def hidden_cursor(file):
+    # type: (IO[Any]) -> Iterator[None]
+    # The Windows terminal does not support the hide/show cursor ANSI codes,
+    # even via colorama. So don't even try.
+    if WINDOWS:
+        yield
+    # We don't want to clutter the output with control characters if we're
+    # writing to a file, or if the user is running with --quiet.
+    # See https://github.com/pypa/pip/issues/3418
+    elif not file.isatty() or logger.getEffectiveLevel() > logging.INFO:
+        yield
+    else:
+        file.write(HIDE_CURSOR)
+        try:
+            yield
+        finally:
+            file.write(SHOW_CURSOR)
+
+
+class RateLimiter(object):
+    def __init__(self, min_update_interval_seconds):
+        # type: (float) -> None
+        self._min_update_interval_seconds = min_update_interval_seconds
+        self._last_update = 0  # type: float
+
+    def ready(self):
+        # type: () -> bool
+        now = time.time()
+        delta = now - self._last_update
+        return delta >= self._min_update_interval_seconds
+
+    def reset(self):
+        # type: () -> None
+        self._last_update = time.time()
+
+
+class SpinnerInterface(object):
+    def spin(self):
+        # type: () -> None
+        raise NotImplementedError()
+
+    def finish(self, final_status):
+        # type: (str) -> None
+        raise NotImplementedError()
+
+
+class InteractiveSpinner(SpinnerInterface):
+    def __init__(self, message, file=None, spin_chars="-\\|/",
+                 # Empirically, 8 updates/second looks nice
+                 min_update_interval_seconds=0.125):
+        self._message = message
+        if file is None:
+            file = sys.stdout
+        self._file = file
+        self._rate_limiter = RateLimiter(min_update_interval_seconds)
+        self._finished = False
+
+        self._spin_cycle = itertools.cycle(spin_chars)
+
+        self._file.write(" " * get_indentation() + self._message + " ... ")
+        self._width = 0
+
+    def _write(self, status):
+        assert not self._finished
+        # Erase what we wrote before by backspacing to the beginning, writing
+        # spaces to overwrite the old text, and then backspacing again
+        backup = "\b" * self._width
+        self._file.write(backup + " " * self._width + backup)
+        # Now we have a blank slate to add our status
+        self._file.write(status)
+        self._width = len(status)
+        self._file.flush()
+        self._rate_limiter.reset()
+
+    def spin(self):
+        # type: () -> None
+        if self._finished:
+            return
+        if not self._rate_limiter.ready():
+            return
+        self._write(next(self._spin_cycle))
+
+    def finish(self, final_status):
+        # type: (str) -> None
+        if self._finished:
+            return
+        self._write(final_status)
+        self._file.write("\n")
+        self._file.flush()
+        self._finished = True
+
+
+# Used for dumb terminals, non-interactive installs (no tty), etc.
+# We still print updates occasionally (once every 60 seconds by default) to
+# act as a keep-alive for systems like Travis-CI that take lack-of-output as
+# an indication that a task has frozen.
+class NonInteractiveSpinner(SpinnerInterface):
+    def __init__(self, message, min_update_interval_seconds=60):
+        # type: (str, float) -> None
+        self._message = message
+        self._finished = False
+        self._rate_limiter = RateLimiter(min_update_interval_seconds)
+        self._update("started")
+
+    def _update(self, status):
+        assert not self._finished
+        self._rate_limiter.reset()
+        logger.info("%s: %s", self._message, status)
+
+    def spin(self):
+        # type: () -> None
+        if self._finished:
+            return
+        if not self._rate_limiter.ready():
+            return
+        self._update("still running...")
+
+    def finish(self, final_status):
+        # type: (str) -> None
+        if self._finished:
+            return
+        self._update("finished with status '%s'" % (final_status,))
+        self._finished = True
+
+
+@contextlib.contextmanager
+def open_spinner(message):
+    # type: (str) -> Iterator[SpinnerInterface]
+    # Interactive spinner goes directly to sys.stdout rather than being routed
+    # through the logging system, but it acts like it has level INFO,
+    # i.e. it's only displayed if we're at level INFO or better.
+    # Non-interactive spinner goes through the logging system, so it is always
+    # in sync with logging configuration.
+    if sys.stdout.isatty() and logger.getEffectiveLevel() <= logging.INFO:
+        spinner = InteractiveSpinner(message)  # type: SpinnerInterface
+    else:
+        spinner = NonInteractiveSpinner(message)
+    try:
+        with hidden_cursor(sys.stdout):
+            yield spinner
+    except KeyboardInterrupt:
+        spinner.finish("canceled")
+        raise
+    except Exception:
+        spinner.finish("error")
+        raise
+    else:
+        spinner.finish("done")

env/lib/python3.8/site-packages/pip/_internal/utils/unpacking.py

@@ -0,0 +1,272 @@
+"""Utilities related archives.
+"""
+
+# The following comment should be removed at some point in the future.
+# mypy: strict-optional=False
+# mypy: disallow-untyped-defs=False
+
+from __future__ import absolute_import
+
+import logging
+import os
+import shutil
+import stat
+import tarfile
+import zipfile
+
+from pip._internal.exceptions import InstallationError
+from pip._internal.utils.filetypes import (
+    BZ2_EXTENSIONS,
+    TAR_EXTENSIONS,
+    XZ_EXTENSIONS,
+    ZIP_EXTENSIONS,
+)
+from pip._internal.utils.misc import ensure_dir
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Iterable, List, Optional, Text, Union
+
+
+logger = logging.getLogger(__name__)
+
+
+SUPPORTED_EXTENSIONS = ZIP_EXTENSIONS + TAR_EXTENSIONS
+
+try:
+    import bz2  # noqa
+    SUPPORTED_EXTENSIONS += BZ2_EXTENSIONS
+except ImportError:
+    logger.debug('bz2 module is not available')
+
+try:
+    # Only for Python 3.3+
+    import lzma  # noqa
+    SUPPORTED_EXTENSIONS += XZ_EXTENSIONS
+except ImportError:
+    logger.debug('lzma module is not available')
+
+
+def current_umask():
+    """Get the current umask which involves having to set it temporarily."""
+    mask = os.umask(0)
+    os.umask(mask)
+    return mask
+
+
+def split_leading_dir(path):
+    # type: (Union[str, Text]) -> List[Union[str, Text]]
+    path = path.lstrip('/').lstrip('\\')
+    if (
+        '/' in path and (
+            ('\\' in path and path.find('/') < path.find('\\')) or
+            '\\' not in path
+        )
+    ):
+        return path.split('/', 1)
+    elif '\\' in path:
+        return path.split('\\', 1)
+    else:
+        return [path, '']
+
+
+def has_leading_dir(paths):
+    # type: (Iterable[Union[str, Text]]) -> bool
+    """Returns true if all the paths have the same leading path name
+    (i.e., everything is in one subdirectory in an archive)"""
+    common_prefix = None
+    for path in paths:
+        prefix, rest = split_leading_dir(path)
+        if not prefix:
+            return False
+        elif common_prefix is None:
+            common_prefix = prefix
+        elif prefix != common_prefix:
+            return False
+    return True
+
+
+def is_within_directory(directory, target):
+    # type: ((Union[str, Text]), (Union[str, Text])) -> bool
+    """
+    Return true if the absolute path of target is within the directory
+    """
+    abs_directory = os.path.abspath(directory)
+    abs_target = os.path.abspath(target)
+
+    prefix = os.path.commonprefix([abs_directory, abs_target])
+    return prefix == abs_directory
+
+
+def unzip_file(filename, location, flatten=True):
+    # type: (str, str, bool) -> None
+    """
+    Unzip the file (with path `filename`) to the destination `location`.  All
+    files are written based on system defaults and umask (i.e. permissions are
+    not preserved), except that regular file members with any execute
+    permissions (user, group, or world) have "chmod +x" applied after being
+    written. Note that for windows, any execute changes using os.chmod are
+    no-ops per the python docs.
+    """
+    ensure_dir(location)
+    zipfp = open(filename, 'rb')
+    try:
+        zip = zipfile.ZipFile(zipfp, allowZip64=True)
+        leading = has_leading_dir(zip.namelist()) and flatten
+        for info in zip.infolist():
+            name = info.filename
+            fn = name
+            if leading:
+                fn = split_leading_dir(name)[1]
+            fn = os.path.join(location, fn)
+            dir = os.path.dirname(fn)
+            if not is_within_directory(location, fn):
+                message = (
+                    'The zip file ({}) has a file ({}) trying to install '
+                    'outside target directory ({})'
+                )
+                raise InstallationError(message.format(filename, fn, location))
+            if fn.endswith('/') or fn.endswith('\\'):
+                # A directory
+                ensure_dir(fn)
+            else:
+                ensure_dir(dir)
+                # Don't use read() to avoid allocating an arbitrarily large
+                # chunk of memory for the file's content
+                fp = zip.open(name)
+                try:
+                    with open(fn, 'wb') as destfp:
+                        shutil.copyfileobj(fp, destfp)
+                finally:
+                    fp.close()
+                    mode = info.external_attr >> 16
+                    # if mode and regular file and any execute permissions for
+                    # user/group/world?
+                    if mode and stat.S_ISREG(mode) and mode & 0o111:
+                        # make dest file have execute for user/group/world
+                        # (chmod +x) no-op on windows per python docs
+                        os.chmod(fn, (0o777 - current_umask() | 0o111))
+    finally:
+        zipfp.close()
+
+
+def untar_file(filename, location):
+    # type: (str, str) -> None
+    """
+    Untar the file (with path `filename`) to the destination `location`.
+    All files are written based on system defaults and umask (i.e. permissions
+    are not preserved), except that regular file members with any execute
+    permissions (user, group, or world) have "chmod +x" applied after being
+    written.  Note that for windows, any execute changes using os.chmod are
+    no-ops per the python docs.
+    """
+    ensure_dir(location)
+    if filename.lower().endswith('.gz') or filename.lower().endswith('.tgz'):
+        mode = 'r:gz'
+    elif filename.lower().endswith(BZ2_EXTENSIONS):
+        mode = 'r:bz2'
+    elif filename.lower().endswith(XZ_EXTENSIONS):
+        mode = 'r:xz'
+    elif filename.lower().endswith('.tar'):
+        mode = 'r'
+    else:
+        logger.warning(
+            'Cannot determine compression type for file %s', filename,
+        )
+        mode = 'r:*'
+    tar = tarfile.open(filename, mode)
+    try:
+        leading = has_leading_dir([
+            member.name for member in tar.getmembers()
+        ])
+        for member in tar.getmembers():
+            fn = member.name
+            if leading:
+                # https://github.com/python/mypy/issues/1174
+                fn = split_leading_dir(fn)[1]  # type: ignore
+            path = os.path.join(location, fn)
+            if not is_within_directory(location, path):
+                message = (
+                    'The tar file ({}) has a file ({}) trying to install '
+                    'outside target directory ({})'
+                )
+                raise InstallationError(
+                    message.format(filename, path, location)
+                )
+            if member.isdir():
+                ensure_dir(path)
+            elif member.issym():
+                try:
+                    # https://github.com/python/typeshed/issues/2673
+                    tar._extract_member(member, path)  # type: ignore
+                except Exception as exc:
+                    # Some corrupt tar files seem to produce this
+                    # (specifically bad symlinks)
+                    logger.warning(
+                        'In the tar file %s the member %s is invalid: %s',
+                        filename, member.name, exc,
+                    )
+                    continue
+            else:
+                try:
+                    fp = tar.extractfile(member)
+                except (KeyError, AttributeError) as exc:
+                    # Some corrupt tar files seem to produce this
+                    # (specifically bad symlinks)
+                    logger.warning(
+                        'In the tar file %s the member %s is invalid: %s',
+                        filename, member.name, exc,
+                    )
+                    continue
+                ensure_dir(os.path.dirname(path))
+                with open(path, 'wb') as destfp:
+                    shutil.copyfileobj(fp, destfp)
+                fp.close()
+                # Update the timestamp (useful for cython compiled files)
+                # https://github.com/python/typeshed/issues/2673
+                tar.utime(member, path)  # type: ignore
+                # member have any execute permissions for user/group/world?
+                if member.mode & 0o111:
+                    # make dest file have execute for user/group/world
+                    # no-op on windows per python docs
+                    os.chmod(path, (0o777 - current_umask() | 0o111))
+    finally:
+        tar.close()
+
+
+def unpack_file(
+        filename,  # type: str
+        location,  # type: str
+        content_type=None,  # type: Optional[str]
+):
+    # type: (...) -> None
+    filename = os.path.realpath(filename)
+    if (
+        content_type == 'application/zip' or
+        filename.lower().endswith(ZIP_EXTENSIONS) or
+        zipfile.is_zipfile(filename)
+    ):
+        unzip_file(
+            filename,
+            location,
+            flatten=not filename.endswith('.whl')
+        )
+    elif (
+        content_type == 'application/x-gzip' or
+        tarfile.is_tarfile(filename) or
+        filename.lower().endswith(
+            TAR_EXTENSIONS + BZ2_EXTENSIONS + XZ_EXTENSIONS
+        )
+    ):
+        untar_file(filename, location)
+    else:
+        # FIXME: handle?
+        # FIXME: magic signatures?
+        logger.critical(
+            'Cannot unpack file %s (downloaded from %s, content-type: %s); '
+            'cannot detect archive format',
+            filename, location, content_type,
+        )
+        raise InstallationError(
+            'Cannot determine archive format of {}'.format(location)
+        )

env/lib/python3.8/site-packages/pip/_internal/utils/urls.py

@@ -0,0 +1,54 @@
+import os
+import sys
+
+from pip._vendor.six.moves.urllib import parse as urllib_parse
+from pip._vendor.six.moves.urllib import request as urllib_request
+
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Optional, Text, Union
+
+
+def get_url_scheme(url):
+    # type: (Union[str, Text]) -> Optional[Text]
+    if ':' not in url:
+        return None
+    return url.split(':', 1)[0].lower()
+
+
+def path_to_url(path):
+    # type: (Union[str, Text]) -> str
+    """
+    Convert a path to a file: URL.  The path will be made absolute and have
+    quoted path parts.
+    """
+    path = os.path.normpath(os.path.abspath(path))
+    url = urllib_parse.urljoin('file:', urllib_request.pathname2url(path))
+    return url
+
+
+def url_to_path(url):
+    # type: (str) -> str
+    """
+    Convert a file: URL to a path.
+    """
+    assert url.startswith('file:'), (
+        "You can only turn file: urls into filenames (not %r)" % url)
+
+    _, netloc, path, _, _ = urllib_parse.urlsplit(url)
+
+    if not netloc or netloc == 'localhost':
+        # According to RFC 8089, same as empty authority.
+        netloc = ''
+    elif sys.platform == 'win32':
+        # If we have a UNC path, prepend UNC share notation.
+        netloc = '\\\\' + netloc
+    else:
+        raise ValueError(
+            'non-local file URIs are not supported on this platform: %r'
+            % url
+        )
+
+    path = urllib_request.url2pathname(netloc + path)
+    return path

env/lib/python3.8/site-packages/pip/_internal/utils/virtualenv.py

@@ -0,0 +1,115 @@
+from __future__ import absolute_import
+
+import logging
+import os
+import re
+import site
+import sys
+
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import List, Optional
+
+logger = logging.getLogger(__name__)
+_INCLUDE_SYSTEM_SITE_PACKAGES_REGEX = re.compile(
+    r"include-system-site-packages\s*=\s*(?P<value>true|false)"
+)
+
+
+def _running_under_venv():
+    # type: () -> bool
+    """Checks if sys.base_prefix and sys.prefix match.
+
+    This handles PEP 405 compliant virtual environments.
+    """
+    return sys.prefix != getattr(sys, "base_prefix", sys.prefix)
+
+
+def _running_under_regular_virtualenv():
+    # type: () -> bool
+    """Checks if sys.real_prefix is set.
+
+    This handles virtual environments created with pypa's virtualenv.
+    """
+    # pypa/virtualenv case
+    return hasattr(sys, 'real_prefix')
+
+
+def running_under_virtualenv():
+    # type: () -> bool
+    """Return True if we're running inside a virtualenv, False otherwise.
+    """
+    return _running_under_venv() or _running_under_regular_virtualenv()
+
+
+def _get_pyvenv_cfg_lines():
+    # type: () -> Optional[List[str]]
+    """Reads {sys.prefix}/pyvenv.cfg and returns its contents as list of lines
+
+    Returns None, if it could not read/access the file.
+    """
+    pyvenv_cfg_file = os.path.join(sys.prefix, 'pyvenv.cfg')
+    try:
+        with open(pyvenv_cfg_file) as f:
+            return f.read().splitlines()  # avoids trailing newlines
+    except IOError:
+        return None
+
+
+def _no_global_under_venv():
+    # type: () -> bool
+    """Check `{sys.prefix}/pyvenv.cfg` for system site-packages inclusion
+
+    PEP 405 specifies that when system site-packages are not supposed to be
+    visible from a virtual environment, `pyvenv.cfg` must contain the following
+    line:
+
+        include-system-site-packages = false
+
+    Additionally, log a warning if accessing the file fails.
+    """
+    cfg_lines = _get_pyvenv_cfg_lines()
+    if cfg_lines is None:
+        # We're not in a "sane" venv, so assume there is no system
+        # site-packages access (since that's PEP 405's default state).
+        logger.warning(
+            "Could not access 'pyvenv.cfg' despite a virtual environment "
+            "being active. Assuming global site-packages is not accessible "
+            "in this environment."
+        )
+        return True
+
+    for line in cfg_lines:
+        match = _INCLUDE_SYSTEM_SITE_PACKAGES_REGEX.match(line)
+        if match is not None and match.group('value') == 'false':
+            return True
+    return False
+
+
+def _no_global_under_regular_virtualenv():
+    # type: () -> bool
+    """Check if "no-global-site-packages.txt" exists beside site.py
+
+    This mirrors logic in pypa/virtualenv for determining whether system
+    site-packages are visible in the virtual environment.
+    """
+    site_mod_dir = os.path.dirname(os.path.abspath(site.__file__))
+    no_global_site_packages_file = os.path.join(
+        site_mod_dir, 'no-global-site-packages.txt',
+    )
+    return os.path.exists(no_global_site_packages_file)
+
+
+def virtualenv_no_global():
+    # type: () -> bool
+    """Returns a boolean, whether running in venv with no system site-packages.
+    """
+
+    if _running_under_regular_virtualenv():
+        return _no_global_under_regular_virtualenv()
+
+    if _running_under_venv():
+        return _no_global_under_venv()
+
+    return False

env/lib/python3.8/site-packages/pip/_internal/utils/wheel.py

@@ -0,0 +1,225 @@
+"""Support functions for working with wheel files.
+"""
+
+from __future__ import absolute_import
+
+import logging
+from email.parser import Parser
+from zipfile import ZipFile
+
+from pip._vendor.packaging.utils import canonicalize_name
+from pip._vendor.pkg_resources import DistInfoDistribution
+from pip._vendor.six import PY2, ensure_str
+
+from pip._internal.exceptions import UnsupportedWheel
+from pip._internal.utils.pkg_resources import DictMetadata
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from email.message import Message
+    from typing import Dict, Tuple
+
+    from pip._vendor.pkg_resources import Distribution
+
+if PY2:
+    from zipfile import BadZipfile as BadZipFile
+else:
+    from zipfile import BadZipFile
+
+
+VERSION_COMPATIBLE = (1, 0)
+
+
+logger = logging.getLogger(__name__)
+
+
+class WheelMetadata(DictMetadata):
+    """Metadata provider that maps metadata decoding exceptions to our
+    internal exception type.
+    """
+    def __init__(self, metadata, wheel_name):
+        # type: (Dict[str, bytes], str) -> None
+        super(WheelMetadata, self).__init__(metadata)
+        self._wheel_name = wheel_name
+
+    def get_metadata(self, name):
+        # type: (str) -> str
+        try:
+            return super(WheelMetadata, self).get_metadata(name)
+        except UnicodeDecodeError as e:
+            # Augment the default error with the origin of the file.
+            raise UnsupportedWheel(
+                "Error decoding metadata for {}: {}".format(
+                    self._wheel_name, e
+                )
+            )
+
+
+def pkg_resources_distribution_for_wheel(wheel_zip, name, location):
+    # type: (ZipFile, str, str) -> Distribution
+    """Get a pkg_resources distribution given a wheel.
+
+    :raises UnsupportedWheel: on any errors
+    """
+    info_dir, _ = parse_wheel(wheel_zip, name)
+
+    metadata_files = [
+        p for p in wheel_zip.namelist() if p.startswith("{}/".format(info_dir))
+    ]
+
+    metadata_text = {}  # type: Dict[str, bytes]
+    for path in metadata_files:
+        # If a flag is set, namelist entries may be unicode in Python 2.
+        # We coerce them to native str type to match the types used in the rest
+        # of the code. This cannot fail because unicode can always be encoded
+        # with UTF-8.
+        full_path = ensure_str(path)
+        _, metadata_name = full_path.split("/", 1)
+
+        try:
+            metadata_text[metadata_name] = read_wheel_metadata_file(
+                wheel_zip, full_path
+            )
+        except UnsupportedWheel as e:
+            raise UnsupportedWheel(
+                "{} has an invalid wheel, {}".format(name, str(e))
+            )
+
+    metadata = WheelMetadata(metadata_text, location)
+
+    return DistInfoDistribution(
+        location=location, metadata=metadata, project_name=name
+    )
+
+
+def parse_wheel(wheel_zip, name):
+    # type: (ZipFile, str) -> Tuple[str, Message]
+    """Extract information from the provided wheel, ensuring it meets basic
+    standards.
+
+    Returns the name of the .dist-info directory and the parsed WHEEL metadata.
+    """
+    try:
+        info_dir = wheel_dist_info_dir(wheel_zip, name)
+        metadata = wheel_metadata(wheel_zip, info_dir)
+        version = wheel_version(metadata)
+    except UnsupportedWheel as e:
+        raise UnsupportedWheel(
+            "{} has an invalid wheel, {}".format(name, str(e))
+        )
+
+    check_compatibility(version, name)
+
+    return info_dir, metadata
+
+
+def wheel_dist_info_dir(source, name):
+    # type: (ZipFile, str) -> str
+    """Returns the name of the contained .dist-info directory.
+
+    Raises AssertionError or UnsupportedWheel if not found, >1 found, or
+    it doesn't match the provided name.
+    """
+    # Zip file path separators must be /
+    subdirs = list(set(p.split("/")[0] for p in source.namelist()))
+
+    info_dirs = [s for s in subdirs if s.endswith('.dist-info')]
+
+    if not info_dirs:
+        raise UnsupportedWheel(".dist-info directory not found")
+
+    if len(info_dirs) > 1:
+        raise UnsupportedWheel(
+            "multiple .dist-info directories found: {}".format(
+                ", ".join(info_dirs)
+            )
+        )
+
+    info_dir = info_dirs[0]
+
+    info_dir_name = canonicalize_name(info_dir)
+    canonical_name = canonicalize_name(name)
+    if not info_dir_name.startswith(canonical_name):
+        raise UnsupportedWheel(
+            ".dist-info directory {!r} does not start with {!r}".format(
+                info_dir, canonical_name
+            )
+        )
+
+    # Zip file paths can be unicode or str depending on the zip entry flags,
+    # so normalize it.
+    return ensure_str(info_dir)
+
+
+def read_wheel_metadata_file(source, path):
+    # type: (ZipFile, str) -> bytes
+    try:
+        return source.read(path)
+        # BadZipFile for general corruption, KeyError for missing entry,
+        # and RuntimeError for password-protected files
+    except (BadZipFile, KeyError, RuntimeError) as e:
+        raise UnsupportedWheel(
+            "could not read {!r} file: {!r}".format(path, e)
+        )
+
+
+def wheel_metadata(source, dist_info_dir):
+    # type: (ZipFile, str) -> Message
+    """Return the WHEEL metadata of an extracted wheel, if possible.
+    Otherwise, raise UnsupportedWheel.
+    """
+    path = "{}/WHEEL".format(dist_info_dir)
+    # Zip file path separators must be /
+    wheel_contents = read_wheel_metadata_file(source, path)
+
+    try:
+        wheel_text = ensure_str(wheel_contents)
+    except UnicodeDecodeError as e:
+        raise UnsupportedWheel("error decoding {!r}: {!r}".format(path, e))
+
+    # FeedParser (used by Parser) does not raise any exceptions. The returned
+    # message may have .defects populated, but for backwards-compatibility we
+    # currently ignore them.
+    return Parser().parsestr(wheel_text)
+
+
+def wheel_version(wheel_data):
+    # type: (Message) -> Tuple[int, ...]
+    """Given WHEEL metadata, return the parsed Wheel-Version.
+    Otherwise, raise UnsupportedWheel.
+    """
+    version_text = wheel_data["Wheel-Version"]
+    if version_text is None:
+        raise UnsupportedWheel("WHEEL is missing Wheel-Version")
+
+    version = version_text.strip()
+
+    try:
+        return tuple(map(int, version.split('.')))
+    except ValueError:
+        raise UnsupportedWheel("invalid Wheel-Version: {!r}".format(version))
+
+
+def check_compatibility(version, name):
+    # type: (Tuple[int, ...], str) -> None
+    """Raises errors or warns if called with an incompatible Wheel-Version.
+
+    Pip should refuse to install a Wheel-Version that's a major series
+    ahead of what it's compatible with (e.g 2.0 > 1.1); and warn when
+    installing a version only minor version ahead (e.g 1.2 > 1.1).
+
+    version: a 2-tuple representing a Wheel-Version (Major, Minor)
+    name: name of wheel or package to raise exception about
+
+    :raises UnsupportedWheel: when an incompatible Wheel-Version is given
+    """
+    if version[0] > VERSION_COMPATIBLE[0]:
+        raise UnsupportedWheel(
+            "%s's Wheel-Version (%s) is not compatible with this version "
+            "of pip" % (name, '.'.join(map(str, version)))
+        )
+    elif version > VERSION_COMPATIBLE:
+        logger.warning(
+            'Installing from a newer Wheel-Version (%s)',
+            '.'.join(map(str, version)),
+        )