Issue #17586: fix typo in contextlib.rst
#6698: IDLE now opens just an editor window when configured to do so.
#6698: merge with 3.3.
Issue #14135: Make sure tests don't leave the locale changed for any
category.

Thanks to Westley Martinez for trying to fix the issue and Atsuo
Ishimoto for an initial patch.
Backed out changeset 4fcd50a6dca7 as it totally breaks the test suite here.
Issue #17483: remove unreachable code in urlopen().
Issue #17357: Add missing verbosity messages when running under
-v/-vv that were lost in the transition to importlib.
merge
merge
Issue #14135: Let's try this again.
list slotdefs in offset order rather than sorting them (closes #17610)

This means we can remove our usage of qsort() than relied on undefined behavior.
merge 3.3 (#17610)