def test_function_when_n_bigger_than_three(self):
result = nth_fib_lists([1, 2], [3, 4], 4)
self.assertEqual([1, 2, 3, 4, 3, 4], result)
def test_if_function_returns_length_of_list(self):
self.assertEqual([], nth_fib_lists([], [], 4))
def test_if_function_returns_B_when_n_equals_two(self):
result = nth_fib_lists([1, 2], [3, 4], 2)
self.assertEqual([3, 4], result)