Class Methods In Python

NITIN GUPTA

 Syntax:

class myClass:
    @classmethod
    def myfunc (cls, arg1, arg2, ...):
                          ....

myfunc defines the function that needs to be converted into a class method

returns: @classmethod returns a class method for function.

Because the class method only has access to the cls argument, it cannot modify the object instance state. However, class methods can still modify the class state that applies to all instances of the class. So a class method automatically recognizes a class, so the only parameter that remains to be passed is the function that needs conversion.

@classmethod Decorator:

 We have covered decorators in detail in Tutorial #51, so here we are just doing to define the functionality of decorators instead of its working. A @classmethod Decorator is a built-in function in Python. It can be applied to any method of the class. We can change the value of variables using this method too.

Differences between Class Method and Static Method:

Class method

Static Method

Taking a class or, in short, form cls as an argument is a must for a class method.

There is no such restriction of any specific parameter related to class in the Static method.

With the help of class methods, we can change and alter the variables of the class.

With a static method, we can not change or alter the class state.

Class methods are restricted to OOPs, so we can only use them if a class exists.

The static method is not restricted to a class.

We generally use class methods to create factory methods. Factory methods return a class object which is similar to a constructor for different use cases.

Static methods are used to create utility functions.

A quick overview:

The Python class method is a way to define a function for the Python class. It receives the class as an implicit first argument. Using @classmethod decorator, creating as many constructors for a class that behaves like a factory constructor is possible. Hopefully, now you can apply this concept to your projects and use it to improve your code's organization and quality.

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