[2.7] bpo-30727: Fix a race condition in test_threading. (GH-2334).#2353

serhiy-storchaka merged 2 commits intopython:2.7python/cpython:2.7from

serhiy-storchaka:backport-32cb968-2.7serhiy-storchaka/cpython:backport-32cb968-2.7Copy head branch name to clipboard