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

Understanding the Differences between @staticmethod and @classmethod Decorators in Python

The @staticmethod and @classmethod decorators in Python allow you to create class-level methods with different behaviors. Here's a detailed explanation of their key differences:

Calling Conventions:

• @staticmethod: Static methods are not bound to any specific instance or class. They behave like regular functions that can be called directly from both instances and classes.
• @classmethod: Class methods are bound to the class itself, rather than to a particular instance. They are typically used to perform operations on the class itself, such as modifying attributes or creating alternative constructors.

Method Signatures:

• Static methods do not receive the class or instance as an implicit first argument.
• Class methods receive the class as the first implicit argument.
• Instance methods (methods without decorators) receive the instance as the first implicit argument.

Instantiation:

• Static methods can be called without creating an instance of the class.
• Class methods can be called from both instances and classes.
• Instance methods can only be called from instances of the class.

Practical Example:

Consider the following code snippet:

class A(object):
    def foo(self, x):
        print("executing foo({self}, {x})")

    @classmethod
    def class_foo(cls, x):
        print("executing class_foo({cls}, {x})")

    @staticmethod
    def static_foo(x):
        print("executing static_foo({x})")

a = A()

When calling foo, the instance a is implicitly passed as the first argument:

a.foo(1)
# executing foo(<__main__.a object at>, 1)</__main__.a>

With class methods, the class of the instance is implicitly passed instead of self:

a.class_foo(1)
# executing class_foo(<class>, 1)</class>

Static methods do not receive any implicit arguments:

a.static_foo(1)
# executing static_foo(1)

Summary:

• @staticmethod decorators create methods that behave like regular functions, without any implicit class or instance binding.
• @classmethod decorators create methods that are bound to the class itself, allowing them to modify class attributes or create alternative constructors.

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