How to Use Class Variables and Methods in Python?

How to Implement Class Variables and Methods in Python

In Python, class (static) variables or methods are used to manage attributes and behaviors that belong to the class itself, rather than to individual instances.

Class Variables

Variables declared within the class definition, but not inside a method, become class (static) variables. For example:

class MyClass:
    i = 3

The i variable is now accessible through the class name:

MyClass.i
3

Note that class variables are distinct from instance-level variables. For instance, you could have:

m = MyClass()
m.i = 4

# Outputs (3, 4)
print(MyClass.i, m.i)

Class Methods

To define class methods, use the @staticmethod decorator before the method definition. Class methods do not receive any instance as an argument, but they can access and modify class-level variables, such as:

class C:
    @staticmethod
    def f(arg1, arg2, ...): ...

Classmethods vs. Staticmethods

@beidy recommends using classmethods over staticmethods, as classmethods receive the class type as the first argument, providing additional flexibility:

class MyClass:
    @classmethod
    def f(cls, arg1, arg2, ...): ...

Using classmethods allows better control and interaction with class data and behavior.

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