def assertDictSubsets(self, sets, subsets):
        """
        For each pair of corresponding elements in C{sets} and C{subsets},
        assert that the element from C{subsets} is a subset of the element from
        C{sets}.
        """
        self.assertEqual(len(sets), len(subsets))
        for a, b in zip(sets, subsets):
            self.assertDictSubset(a, b)

        For each pair of corresponding elements in C{sets} and C{subsets},
        assert that the element from C{subsets} is a subset of the element from
        C{sets}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/trial/test/test_warning.py