Utilizing Class Methods

Class Method is a method that takes the class itself as the first argument when executed.

It's used to access class variables or perform operations at the class level.

Class methods are defined with the @classmethod decorator (a function that wraps another function, extending the wrapped function's capabilities).

Class methods receive the class itself as the first parameter (cls) rather than an instance (self).

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class MyClass:
    # Class variable
    class_variable = "Common value"

    # Define class method
    @classmethod
    def class_method(cls):
        return f"Class method call: {cls.class_variable}"

In the code above, class_method is a class method that accesses the class variable through the cls parameter.

Class methods can be called using either the class name or an instance.

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# Call with class name
print(MyClass.class_method())
# Output: Class method call: Common value

# Call through an instance
instance = MyClass()
print(instance.class_method())
# Output: Class method call: Common value

Class methods are mainly used to read or modify class variables.

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class Counter:
    count = 0  # Class variable

    @classmethod
    def increment(cls):
        cls.count += 1
        return cls.count

# Call class method
print(Counter.increment())
# Output: 1
print(Counter.increment())
# Output: 2

Class methods cannot change the state of an instance (instance variables) and should be used to manipulate class variables or the class itself.