def test_order(self):
        assert (event.Priority.PRE_CORE
                > event.Priority.CORE
                > event.Priority.POST_CORE
                > event.Priority.PRE_DEFAULT
                > event.Priority.DEFAULT
                > event.Priority.POST_DEFAULT)
def test_impl(n):
            df = pd.DataFrame({'A': np.ones(n), 'B': np.random.ranf(n)})
            Ac = df.A.cumsum()
            return Ac.sum()