classThreadSafeCleanupTestCase:"""Subclass of unittest.TestCase with thread-safe cleanup methods.    This subclass protects the addCleanup() and doCleanups() methods    with a recursive lock.    """def__init__(self,*args,**kwargs):super().__init__(*args,**kwargs)self._cleanup_lock=threading.RLock()defaddCleanup(self,*args,**kwargs):withself._cleanup_lock:returnsuper().addCleanup(*args,**kwargs)defdoCleanups(self,*args,**kwargs):withself._cleanup_lock:returnsuper().doCleanups(*args,**kwargs)

0:40:31 load avg: 3.05 [337/467/1] test_socket worker non-zero exit code (Exit code 1) -- running (1): test_math (1 min 4 sec)Timeout (0:40:00)!Thread 0xf5dea440 (most recent call first):  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/test/test_socket.py", line 230 in addCleanup  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/test/test_socket.py", line 3576 in newFDs  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/test/test_socket.py", line 3611 in createAndSendFDs  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/test/test_socket.py", line 3841 in _testCmsgTrunc0  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/test/test_socket.py", line 402 in clientRunThread 0xf7acb040 (most recent call first):  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/threading.py", line 348 in wait  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/threading.py", line 648 in wait  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/case.py", line 597 in _callCleanup  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/case.py", line 673 in doCleanups  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/test/test_socket.py", line 235 in doCleanups  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/case.py", line 640 in run  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/case.py", line 692 in __call__  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/suite.py", line 122 in run  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/suite.py", line 84 in __call__  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/suite.py", line 122 in run  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/suite.py", line 84 in __call__  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/suite.py", line 122 in run  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/suite.py", line 84 in __call__  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/unittest/runner.py", line 240 in run  File "/var/lib/buildbot/workers/3.x.gps-raspbian.nondebug/build/Lib/test/support/__init__.py", line 1155 in _run_suite  ...