'L{failure.Failure.cleanFailure} sets the C{__traceback__} attribute of
the exception to L{None} in Python 3.'

def test_cleanFailureRemovesTracebackInPython3(self):

    f = getDivisionFailure()
    self.assertIsNotNone(f.tb)
    self.assertIs(f.value.__traceback__, f.tb)
    f.cleanFailure()
    self.assertIsNone(f.value.__traceback__)
