Patch by Seth Michael Larson.

Patch by Kevin Conway.

Patch by Ed Schouten.

Patch by Eryk Sun.

Not completely mechanical since support for East Asian Width changes—emoji
codepoints became Wide—had to be added to unicodedata.

Patch by Ed Schouten.

Issue #28127: Add a function to check that a dictionary remains consistent
after any change.

By default, tables are not checked, only basic attributes. Define DEBUG_PYDICT
(ex: gcc -D DEBUG_PYDICT) to also check dictionary "content".

Backport of 01ddd608b85c.

zipimport should use the same optimization level as the interpreter.

Issue #28188: Use PyMem_Calloc() to get rid of a type-limits warning and an extra memset() call in _ssl.c.