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Clarrification on @classmethod and cls

Just looking for some clarification on what '@classmethod' and 'cls' actually do and why they are needed as I'm not sure I understand despite completing this task.

1 Answer

Steven Parker
Steven Parker
229,708 Points

A class method is something you would call using the class itself, but a typical method would be called using an instance of the class. So in a typical method, the first argument is a reference to the instance, which is by convention referenced with the name "self".

But in a class method, there is no instance, so the system provides a reference to the class as the first argument. Also as a convention (not enforced technically) this reference is named "cls". This is often used to create a new instance.