@staticmethod and @classmethod

Question

The Python OOP tutorial was quite confusing. Can someone please explain @classmethod and @staticmethod. I am writing more Python programs which are object oriented but @classmethod method and @staticmethod really threw me.

Answer 1

A method normally defined takes 'self' as an implicit first argument.

A classmethod takes the class as an implicit first argument.

You can use this for example when you have class variables (variables that all instances share) like an instance counter.

If a method of an instance tries to change such a class variable by referring to it with self., it will instead override the class variable.

So a class method would be one way to change class content instead of instance content.

As a habit, you use 'cls' now instead of 'self' but it could be anything.

A static method doesn't implicitly pass anything, neither instance nor class. So it is basically the same as a regular free function, only that it's formally part of a class.