Original patches by A. Kuchling and G. Rees (#12691).

constructed examples and all but 7 of the test/test_*.py files (run with -ucpu)
pass. Remove those that fail the new test from the selection list.
Patch partly based on patches by G. Brandl (#8478) and G. Rees (#12691).

Also added the missing documentation for new new option.

Also add the missing TextWrapper.shorten method doc.

Also reflow mmap paragraph.

Issue #20637: Key-sharing now also works for instance dictionaries of subclasses.  Patch by Peter Ingebretson.

I'm documenting this new function, but I'm wondering if this will trigger
someone to think about whether or not this actually makes sense :)

I'll look into re-enabling them in issue #20128.

This addresses issue #20199, if I got it right.  The deprecation and
replacement lists are based on the importlib documentation.

is used as a sentinel () to detect if -1 is really an error or a valid
timestamp. On AIX, tm_wday is unchanged even on success and so cannot be used
as a sentinel.

chance of sporadic failures.

outsize range [1902; 2037].

for bound methods.  Previous to this change, it displayed "self" for methods
implemented in Python but not methods implemented in C; it is now both
internally consistent and consistent with inspect.Signature.

Use the same default timeout than test.bat: 1 hour (3600 seconds).