bpo-34183: Fix running Lib/test/test_contextlib_async.py as a script. (GH-8381) (GH-8422)

(cherry picked from commit db8e3a1e4476620b2b5aaf57acfc3ef58a08213b)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
1 file changed