[3.8] bpo-43842: Fix race condition in test_logging SMTP test (GH-25436) (GH-25437) by vstinner · Pull Request #25440 · python/cpython

Fix a race condition in the SMTP test of test_logging. Don't close a
file descriptor (socket) from a different thread while
asyncore.loop() is polling the file descriptor.

(cherry picked from commit 75ec103)
(cherry picked from commit e1903e1)

https://bugs.python.org/issue43842