def test_intersection(self): abcd = ['a', 'b', 'c', 'd'] efgh = ['e', 'f', 'g', 'h'] fedc = ['c', 'd', 'e', 'f'] # cdef is cython keyword O_o) feed = ['f', 'e', 'e', 'd'] self.assertEqual(intersection(abcd, efgh), []) self.assertEqual(intersection(abcd, fedc), ['c', 'd']) self.assertEqual(intersection(feed, feed), feed) self.assertEqual(intersection([], []), []) self.assertEqual(intersection(feed, fedc), feed) self.assertEqual(intersection(fedc, feed), ['d', 'e', 'f']) self.assertEqual(intersection(feed, efgh), ['f', 'e', 'e'])