def test_split_by(self) -> None: """Utility function primarily used in authors page""" flat_list = [1, 2, 3, 4, 5, 6, 7, 8, 9] expected_result = [[1, 2, 3], [4, 5, 6], [7, 8, 9]] self.assertEqual(split_by(flat_list, 3, None), expected_result)