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

venv/lib/python3.9/site-packages/setuptools/errors.py

@@ -0,0 +1,16 @@
+"""setuptools.errors
+
+Provides exceptions used by setuptools modules.
+"""
+
+from distutils.errors import DistutilsError
+
+
+class RemovedCommandError(DistutilsError, RuntimeError):
+    """Error used for commands that have been removed in setuptools.
+
+    Since ``setuptools`` is built on ``distutils``, simply removing a command
+    from ``setuptools`` will make the behavior fall back to ``distutils``; this
+    error is raised if a command exists in ``distutils`` but has been actively
+    removed in ``setuptools``.
+    """