How to inherit and extend a list object in Python?

Use the super() function to call the method of the base class, or invoke the method directly:

class MyList(list):
    def __getitem__(self, key):
        return list.__getitem__(self, key-1)

class MyList(list):
    def __getitem__(self, key):
        return super(MyList, self).__getitem__(key-1)

However, this will not change the behavior of other list methods. For example, index remains unchanged, which can lead to unexpected results:

numbers = MyList()
numbers.append("one")
numbers.append("two")

print numbers.index('one')
>>> 1

print numbers[numbers.index('one')]
>>> 'two'

Instead, subclass integer using the same method to define all numbers to be minus one from what you set them to. Voila.

Sorry, I had to. It's like the joke about Microsoft defining dark as the standard.

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