--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/planemo/lib/python3.7/site-packages/pip/_internal/utils/outdated.py	Fri Jul 31 00:32:28 2020 -0400
@@ -0,0 +1,178 @@
+from __future__ import absolute_import
+
+import datetime
+import json
+import logging
+import os.path
+import sys
+
+from pip._vendor import lockfile, pkg_resources
+from pip._vendor.packaging import version as packaging_version
+
+from pip._internal.cli.cmdoptions import make_search_scope
+from pip._internal.index import PackageFinder
+from pip._internal.models.selection_prefs import SelectionPreferences
+from pip._internal.utils.compat import WINDOWS
+from pip._internal.utils.filesystem import check_path_owner
+from pip._internal.utils.misc import ensure_dir, get_installed_version
+from pip._internal.utils.packaging import get_installer
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    import optparse
+    from typing import Any, Dict
+    from pip._internal.download import PipSession
+
+
+SELFCHECK_DATE_FMT = "%Y-%m-%dT%H:%M:%SZ"
+
+
+logger = logging.getLogger(__name__)
+
+
+class SelfCheckState(object):
+    def __init__(self, cache_dir):
+        # type: (str) -> None
+        self.state = {}  # type: Dict[str, Any]
+        self.statefile_path = None
+
+        # Try to load the existing state
+        if cache_dir:
+            self.statefile_path = os.path.join(cache_dir, "selfcheck.json")
+            try:
+                with open(self.statefile_path) as statefile:
+                    self.state = json.load(statefile)[sys.prefix]
+            except (IOError, ValueError, KeyError):
+                # Explicitly suppressing exceptions, since we don't want to
+                # error out if the cache file is invalid.
+                pass
+
+    def save(self, pypi_version, current_time):
+        # type: (str, datetime.datetime) -> None
+        # If we do not have a path to cache in, don't bother saving.
+        if not self.statefile_path:
+            return
+
+        # Check to make sure that we own the directory
+        if not check_path_owner(os.path.dirname(self.statefile_path)):
+            return
+
+        # Now that we've ensured the directory is owned by this user, we'll go
+        # ahead and make sure that all our directories are created.
+        ensure_dir(os.path.dirname(self.statefile_path))
+
+        # Attempt to write out our version check file
+        with lockfile.LockFile(self.statefile_path):
+            if os.path.exists(self.statefile_path):
+                with open(self.statefile_path) as statefile:
+                    state = json.load(statefile)
+            else:
+                state = {}
+
+            state[sys.prefix] = {
+                "last_check": current_time.strftime(SELFCHECK_DATE_FMT),
+                "pypi_version": pypi_version,
+            }
+
+            with open(self.statefile_path, "w") as statefile:
+                json.dump(state, statefile, sort_keys=True,
+                          separators=(",", ":"))
+
+
+def was_installed_by_pip(pkg):
+    # type: (str) -> bool
+    """Checks whether pkg was installed by pip
+
+    This is used not to display the upgrade message when pip is in fact
+    installed by system package manager, such as dnf on Fedora.
+    """
+    try:
+        dist = pkg_resources.get_distribution(pkg)
+        return "pip" == get_installer(dist)
+    except pkg_resources.DistributionNotFound:
+        return False
+
+
+def pip_version_check(session, options):
+    # type: (PipSession, optparse.Values) -> None
+    """Check for an update for pip.
+
+    Limit the frequency of checks to once per week. State is stored either in
+    the active virtualenv or in the user's USER_CACHE_DIR keyed off the prefix
+    of the pip script path.
+    """
+    installed_version = get_installed_version("pip")
+    if not installed_version:
+        return
+
+    pip_version = packaging_version.parse(installed_version)
+    pypi_version = None
+
+    try:
+        state = SelfCheckState(cache_dir=options.cache_dir)
+
+        current_time = datetime.datetime.utcnow()
+        # Determine if we need to refresh the state
+        if "last_check" in state.state and "pypi_version" in state.state:
+            last_check = datetime.datetime.strptime(
+                state.state["last_check"],
+                SELFCHECK_DATE_FMT
+            )
+            if (current_time - last_check).total_seconds() < 7 * 24 * 60 * 60:
+                pypi_version = state.state["pypi_version"]
+
+        # Refresh the version if we need to or just see if we need to warn
+        if pypi_version is None:
+            # Lets use PackageFinder to see what the latest pip version is
+            search_scope = make_search_scope(options, suppress_no_index=True)
+
+            # Pass allow_yanked=False so we don't suggest upgrading to a
+            # yanked version.
+            selection_prefs = SelectionPreferences(
+                allow_yanked=False,
+                allow_all_prereleases=False,  # Explicitly set to False
+            )
+
+            finder = PackageFinder.create(
+                search_scope=search_scope,
+                selection_prefs=selection_prefs,
+                trusted_hosts=options.trusted_hosts,
+                session=session,
+            )
+            candidate = finder.find_candidates("pip").get_best()
+            if candidate is None:
+                return
+            pypi_version = str(candidate.version)
+
+            # save that we've performed a check
+            state.save(pypi_version, current_time)
+
+        remote_version = packaging_version.parse(pypi_version)
+
+        local_version_is_older = (
+            pip_version < remote_version and
+            pip_version.base_version != remote_version.base_version and
+            was_installed_by_pip('pip')
+        )
+
+        # Determine if our pypi_version is older
+        if not local_version_is_older:
+            return
+
+        # Advise "python -m pip" on Windows to avoid issues
+        # with overwriting pip.exe.
+        if WINDOWS:
+            pip_cmd = "python -m pip"
+        else:
+            pip_cmd = "pip"
+        logger.warning(
+            "You are using pip version %s, however version %s is "
+            "available.\nYou should consider upgrading via the "
+            "'%s install --upgrade pip' command.",
+            pip_version, pypi_version, pip_cmd
+        )
+    except Exception:
+        logger.debug(
+            "There was an error checking the latest version of pip",
+            exc_info=True,
+        )