--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/python3.8/site-packages/pip/_internal/utils/compat.py	Mon Jul 27 03:47:31 2020 -0400
@@ -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])