Issue #14110: Fix test failures on FreeBSD if the user is in the wheel group.
Merge 3.3.
Fix docstring typo in concurrent.futures.Future
Issue #16982: Fix --without-threads build failure.
Issue #16987: Fix definition of SHLIB_EXT.
Merge 3.3.
Remove outdated statement
Remove outdated statement
Remove outdated statement
Issue #11870: Skip test_3_join_in_forked_from_thread() on HP-UX.
Merge 3.3.
check windows fd validity (closes #16992)
merge 3.3
math.fsum docs did not show up because of a misplaced testsetup directive
math.fsum docs did not show up because of a misplaced testsetup directive
(merged 3.2 fix)
math.fsum docs did not show up because of a misplaced testsetup directive
(merged 3.2 fix through 3.3)