def test_unexpectedSuccesses(self):
        """
        Ensure that unexpected successes are caught.
        """
        self.suite(self.reporter)
        expectedReasons = ['todo3']
        reasonsGiven = [ r.reason
                         for t, r in self.reporter.unexpectedSuccesses ]
        self.assertEqual(expectedReasons, reasonsGiven)

        Ensure that unexpected successes are caught.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/trial/test/test_tests.py