.. note::

   $ find sphinx tests LICENSE doc/conf.py -type f -exec sed -i '' -e 's/2007\-20../2007-2021/' {} \;
   $ git co sphinx/locale/**/*.js sphinx/templates/epub3/mimetype

Use ismock() to check a module member is a mocked or not. It allows not
to skip subclasses of mocked class.

Linkcheck organizes the URLs to checks in a PriorityQueue. The items are
tuples (priority, url, docname, lineno).

Tuples where the lineno is `None` are not comparable with tuples that
have an integer lineno, and PriorityQueue items must be comparable (see
https://bugs.python.org/issue31145).

Fixes an issue when a document contains two links to the same URL, one
with an int line number and the other without line number metadata (such
as an image :target: attribute).

Using 0 instead of None to represent no line number should not lead to
observable changes, the result logger only logs the line number when it
is truthy.

Close #8565

The instance attributes on subclasses are shown on the document of
parent class unexpectedly because of autodoc modifies `__annotations__`
in place.  This fix creates a copy of `__annotations__` attribute and
attach it to the subclass.

The restify() helper crashes when ForwardRef is passed.

Close #8236: napoleon: Support numpydoc's "Receives" section