How to obtain the last index of a list?

Question

Suppose I\'ve the following list:

list1 = [1, 2, 33, 51]
                    ^
                    |
indices  0  1   2   3

How do I obtain the

Answer 1

len(list1)-1 is definitely the way to go, but if you absolutely need a list that has a function that returns the last index, you could create a class that inherits from list.

class MyList(list):
    def last_index(self):
        return len(self)-1


>>> l=MyList([1, 2, 33, 51])
>>> l.last_index()
3