What's the Difference Between `@classmethod` and `@staticmethod` in Python?

Meaning and Usage of @classmethod and @staticmethod for Beginners

In Python, @classmethod and @staticmethod are decorators used to define methods with specific characteristics.

@classmethod

A classmethod is a method that is bound to a class, not to an individual instance of the class. It must have a class as its first argument, which is typically named cls. By convention, classmethods are named with from_ or create_ prefixes.

When to use @classmethod:

• When you want to create a factory method that returns a new instance of the class.
• When you want to define a method that operates on the class itself, rather than on an instance.

Example:

class Date:
    def __init__(self, day, month, year):
        self.day = day
        self.month = month
        self.year = year

    @classmethod
    def from_string(cls, date_as_string):
        day, month, year = map(int, date_as_string.split('-'))
        return cls(day, month, year)

@staticmethod

A staticmethod is a method that is not bound to either the class or an instance. It does not have access to any instance or class variables. Staticmethods are typically used for utility functions that can be reused without modification.

When to use @staticmethod:

• When you want to define a function that performs some operation but does not depend on the class or instance state.
• When you want to create a function that can be called from any context.

Example:

class Date:
    @staticmethod
    def is_date_valid(date_as_string):
        day, month, year = map(int, date_as_string.split('-'))
        return day <= 31 and month <= 12 and year <= 3999

Difference between @classmethod and @staticmethod

Feature	@classmethod	@staticmethod
Access to class	Has access to the class	No access to the class
Access to instance	No access to instances	No access to instances
Usage	Factory methods, operations on the class	Utility functions, independent of class or instances

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