How to correctly call base class methods (and constructor) from inherited classes in Python?

How to correctly call base class methods (and constructor) from inherited classes in Python?

In Python, you can call base class methods (including the constructor) from inherited classes using the super() function. The super() function allows you to access and invoke methods and constructors of the parent (base) class. Here's how you can correctly call base class methods and constructors:

  1. Calling Base Class Constructors:

    To call the constructor of the base class, use super().__init__() within the constructor of the derived class. This initializes the inherited attributes from the base class.

    class BaseClass: def __init__(self, value): self.value = value class DerivedClass(BaseClass): def __init__(self, value, derived_value): super().__init__(value) # Call the base class constructor self.derived_value = derived_value obj = DerivedClass(10, 20) print(obj.value) # Output: 10 print(obj.derived_value) # Output: 20

  2. Calling Base Class Methods:

    To call a method defined in the base class, use super().method_name() within the method of the derived class. This allows you to reuse and extend the functionality defined in the base class.

    class BaseClass: def base_method(self): print("Base class method") class DerivedClass(BaseClass): def derived_method(self): super().base_method() # Call the base class method print("Derived class method") obj = DerivedClass() obj.derived_method()

    Output:

    Base class method Derived class method

Using super() ensures that you correctly call methods and constructors of the base class in the context of the derived class. It helps maintain proper method resolution order in cases where you have multiple levels of inheritance, and it ensures that all relevant constructors and methods are invoked.

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