* Fix Sphinx warning in library/xml.rstDirect use of the pyexpat module is deprecated, but this is how to check the version for security purposes* Fix Sphinx warning in library/importlib.resources.rst* Use italics for parameters* Link to the exception* Fix Sphinx warning in library/gzip.rst* Document message and header defect base classes to fix Sphinx warning in library/email.headerregistry.rst* Restore feed_eof() doc to fix Sphinx warning in library/asyncio-stream.rst* Fix Sphinx warning in extending/newtypes.rst* Fix Sphinx warning in c-api/set.rstOn stdtypes.rst, set and frozenset are documented together and the frozenset has the working refs(cherry picked from commit3faf8e5)Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>