utilize int.from_bytes
Issue #17741: Rename IncrementalParser and its methods.

The new names are hopefully more descriptive and consistent. If you feel you
don't agree with this change, *please* read issue 17741 first - there's a lot of
discussion in there.
Issue #18418: After fork(), reinit all threads states, not only active ones.
Patch by A. Jesse Jiryu Davis.
Issue #18418: After fork(), reinit all threads states, not only active ones.
Patch by A. Jesse Jiryu Davis.
Forward port new tests from Issue #18851.
Forward port new tests from Issue #18851.