--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/python3.8/site-packages/pip/_internal/cli/base_command.py	Mon Jul 27 03:47:31 2020 -0400
@@ -0,0 +1,226 @@
+"""Base Command class, and related routines"""
+
+from __future__ import absolute_import, print_function
+
+import logging
+import logging.config
+import optparse
+import os
+import platform
+import sys
+import traceback
+
+from pip._internal.cli import cmdoptions
+from pip._internal.cli.command_context import CommandContextMixIn
+from pip._internal.cli.parser import (
+    ConfigOptionParser,
+    UpdatingDefaultsHelpFormatter,
+)
+from pip._internal.cli.status_codes import (
+    ERROR,
+    PREVIOUS_BUILD_DIR_ERROR,
+    SUCCESS,
+    UNKNOWN_ERROR,
+    VIRTUALENV_NOT_FOUND,
+)
+from pip._internal.exceptions import (
+    BadCommand,
+    CommandError,
+    InstallationError,
+    PreviousBuildDirError,
+    UninstallationError,
+)
+from pip._internal.utils.deprecation import deprecated
+from pip._internal.utils.filesystem import check_path_owner
+from pip._internal.utils.logging import BrokenStdoutLoggingError, setup_logging
+from pip._internal.utils.misc import get_prog, normalize_path
+from pip._internal.utils.temp_dir import global_tempdir_manager
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+from pip._internal.utils.virtualenv import running_under_virtualenv
+
+if MYPY_CHECK_RUNNING:
+    from typing import List, Tuple, Any
+    from optparse import Values
+
+__all__ = ['Command']
+
+logger = logging.getLogger(__name__)
+
+
+class Command(CommandContextMixIn):
+    usage = None  # type: str
+    ignore_require_venv = False  # type: bool
+
+    def __init__(self, name, summary, isolated=False):
+        # type: (str, str, bool) -> None
+        super(Command, self).__init__()
+        parser_kw = {
+            'usage': self.usage,
+            'prog': '%s %s' % (get_prog(), name),
+            'formatter': UpdatingDefaultsHelpFormatter(),
+            'add_help_option': False,
+            'name': name,
+            'description': self.__doc__,
+            'isolated': isolated,
+        }
+
+        self.name = name
+        self.summary = summary
+        self.parser = ConfigOptionParser(**parser_kw)
+
+        # Commands should add options to this option group
+        optgroup_name = '%s Options' % self.name.capitalize()
+        self.cmd_opts = optparse.OptionGroup(self.parser, optgroup_name)
+
+        # Add the general options
+        gen_opts = cmdoptions.make_option_group(
+            cmdoptions.general_group,
+            self.parser,
+        )
+        self.parser.add_option_group(gen_opts)
+
+    def handle_pip_version_check(self, options):
+        # type: (Values) -> None
+        """
+        This is a no-op so that commands by default do not do the pip version
+        check.
+        """
+        # Make sure we do the pip version check if the index_group options
+        # are present.
+        assert not hasattr(options, 'no_index')
+
+    def run(self, options, args):
+        # type: (Values, List[Any]) -> Any
+        raise NotImplementedError
+
+    def parse_args(self, args):
+        # type: (List[str]) -> Tuple[Any, Any]
+        # factored out for testability
+        return self.parser.parse_args(args)
+
+    def main(self, args):
+        # type: (List[str]) -> int
+        try:
+            with self.main_context():
+                return self._main(args)
+        finally:
+            logging.shutdown()
+
+    def _main(self, args):
+        # type: (List[str]) -> int
+        # Intentionally set as early as possible so globally-managed temporary
+        # directories are available to the rest of the code.
+        self.enter_context(global_tempdir_manager())
+
+        options, args = self.parse_args(args)
+
+        # Set verbosity so that it can be used elsewhere.
+        self.verbosity = options.verbose - options.quiet
+
+        level_number = setup_logging(
+            verbosity=self.verbosity,
+            no_color=options.no_color,
+            user_log_file=options.log,
+        )
+
+        if (
+            sys.version_info[:2] == (2, 7) and
+            not options.no_python_version_warning
+        ):
+            message = (
+                "A future version of pip will drop support for Python 2.7. "
+                "More details about Python 2 support in pip, can be found at "
+                "https://pip.pypa.io/en/latest/development/release-process/#python-2-support"  # noqa
+            )
+            if platform.python_implementation() == "CPython":
+                message = (
+                    "Python 2.7 reached the end of its life on January "
+                    "1st, 2020. Please upgrade your Python as Python 2.7 "
+                    "is no longer maintained. "
+                ) + message
+            deprecated(message, replacement=None, gone_in=None)
+
+        if options.skip_requirements_regex:
+            deprecated(
+                "--skip-requirements-regex is unsupported and will be removed",
+                replacement=(
+                    "manage requirements/constraints files explicitly, "
+                    "possibly generating them from metadata"
+                ),
+                gone_in="20.1",
+                issue=7297,
+            )
+
+        # TODO: Try to get these passing down from the command?
+        #       without resorting to os.environ to hold these.
+        #       This also affects isolated builds and it should.
+
+        if options.no_input:
+            os.environ['PIP_NO_INPUT'] = '1'
+
+        if options.exists_action:
+            os.environ['PIP_EXISTS_ACTION'] = ' '.join(options.exists_action)
+
+        if options.require_venv and not self.ignore_require_venv:
+            # If a venv is required check if it can really be found
+            if not running_under_virtualenv():
+                logger.critical(
+                    'Could not find an activated virtualenv (required).'
+                )
+                sys.exit(VIRTUALENV_NOT_FOUND)
+
+        if options.cache_dir:
+            options.cache_dir = normalize_path(options.cache_dir)
+            if not check_path_owner(options.cache_dir):
+                logger.warning(
+                    "The directory '%s' or its parent directory is not owned "
+                    "or is not writable by the current user. The cache "
+                    "has been disabled. Check the permissions and owner of "
+                    "that directory. If executing pip with sudo, you may want "
+                    "sudo's -H flag.",
+                    options.cache_dir,
+                )
+                options.cache_dir = None
+
+        try:
+            status = self.run(options, args)
+            # FIXME: all commands should return an exit status
+            # and when it is done, isinstance is not needed anymore
+            if isinstance(status, int):
+                return status
+        except PreviousBuildDirError as exc:
+            logger.critical(str(exc))
+            logger.debug('Exception information:', exc_info=True)
+
+            return PREVIOUS_BUILD_DIR_ERROR
+        except (InstallationError, UninstallationError, BadCommand) as exc:
+            logger.critical(str(exc))
+            logger.debug('Exception information:', exc_info=True)
+
+            return ERROR
+        except CommandError as exc:
+            logger.critical('%s', exc)
+            logger.debug('Exception information:', exc_info=True)
+
+            return ERROR
+        except BrokenStdoutLoggingError:
+            # Bypass our logger and write any remaining messages to stderr
+            # because stdout no longer works.
+            print('ERROR: Pipe to stdout was broken', file=sys.stderr)
+            if level_number <= logging.DEBUG:
+                traceback.print_exc(file=sys.stderr)
+
+            return ERROR
+        except KeyboardInterrupt:
+            logger.critical('Operation cancelled by user')
+            logger.debug('Exception information:', exc_info=True)
+
+            return ERROR
+        except BaseException:
+            logger.critical('Exception:', exc_info=True)
+
+            return UNKNOWN_ERROR
+        finally:
+            self.handle_pip_version_check(options)
+
+        return SUCCESS