There is different failure when run this test separately:

$ ./python -m test -v -m test_coverage test_trace
...
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FAIL: test_coverage (test.test_trace.TestCoverage)
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Traceback (most recent call last):
  File "/home/serhiy/py/cpython/Lib/test/test_trace.py", line 318, in test_coverage
    self.assertIn("pprint.cover", files)
AssertionError: 'pprint.cover' not found in ['warnings.cover', 'unittest.case.cover', 'test.support.__init__.cover', 'test.test_pprint.cover', 'trace.cover', 'platform.cover', 'weakref.cover', 'unittest.loader.cover', 'unittest.util.cover', 'copy.cover', 'unittest.runner.cover', 'unittest.result.cover', 'unittest.suite.cover', 'unittest.signals.cover', 'test.test_set.cover']

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