my_list = [1, 2, [3, 4]] my_list[2].extend([5, 6]) print(my_list)
[1, 2, 5, 6]
[1, 2, [3, 4]]
[1, 2, [3, 4, 5, 6]]
[1, 2, [3, 4, [5, 6]]]