Let a class behave like it's a list in Python

Question

I have a class which is essentially a collection/list of things. But I want to add some extra functions to this list. What I would like, is the following:

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Answer 1

The simplest solution here is to inherit from list class:

class MyFancyList(list):
    def fancyFunc(self):
        # do something fancy

You can then use MyFancyList type as a list, and use its specific methods.

Inheritance introduces a strong coupling between your object and list. The approach you implement is basically a proxy object. The way to use heavily depends of the way you will use the object. If it have to be a list, then inheritance is probably a good choice.

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EDIT: as pointed out by @acdr, some methods returning list copy should be overriden in order to return a MyFancyList instead a list.

A simple way to implement that:

class MyFancyList(list):
    def fancyFunc(self):
        # do something fancy
    def __add__(self, *args, **kwargs):
        return MyFancyList(super().__add__(*args, **kwargs))