how to update list in python

1simple_list = [1,2,3,4]
2
3# append an element
4simple_list.append(5) # now simple_list is [1,2,3,4,5]
5
6# append all the elements of another list (NO NESTING)
7second_list = [6,7,8]
8simple_list.extend(second_list) # now simple_list is [1,2,3,4,5,6,7,8]
9
10# replace an element by simply giving the index and the new element
11simple_list[0] = 100 # now simple_list is [100,2,3,4,5,6,7,8]