'If the Failure has been cleaned, then C{getTracebackObject} returns an
object that looks the same to L{traceback.extract_tb}.'

def test_getTracebackObjectFromClean(self):

    f = getDivisionFailure()
    expected = traceback.extract_tb(f.getTracebackObject())
    f.cleanFailure()
    observed = traceback.extract_tb(f.getTracebackObject())
    self.assertIsNotNone(expected)
    self.assertEqual(expected, observed)
