added pg_setting_export_example_enhanced.py and new method list_vpgs_from_exported_settings in vpgs.py

venv/lib/python3.9/site-packages/pip/_internal/utils/appdirs.py

@@ -0,0 +1,35 @@
+"""
+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.
+"""
+
+import os
+from typing import List
+
+from pip._vendor import appdirs as _appdirs
+
+
+def user_cache_dir(appname: str) -> str:
+    return _appdirs.user_cache_dir(appname, appauthor=False)
+
+
+def user_config_dir(appname: str, roaming: bool = True) -> str:
+    path = _appdirs.user_config_dir(appname, appauthor=False, roaming=roaming)
+    if _appdirs.system == "darwin" and not os.path.isdir(path):
+        path = os.path.expanduser("~/.config/")
+        if appname:
+            path = os.path.join(path, appname)
+    return path
+
+
+# for the discussion regarding site_config_dir locations
+# see <https://github.com/pypa/pip/issues/1733>
+def site_config_dirs(appname: 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]