Overriding Methods & Using super()

Introduction

When a class inherits from another, it doesn’t have to behave exactly the same.

A child class can:

Override methods from the parent class
Change how inherited behaviour works
Extend parent behaviour using super()

This allows programs to stay organised while still being flexible and powerful.

In this lesson, you will learn how to:

Override a method in a child class
Use super() to reuse parent behaviour
Understand when and why overriding is useful

Overriding a Method

A method is overridden when a child class defines a method with the same name as one in the parent.

Python will always use the child version if it exists.

class Parent:
    def greet(self):
        print("Hello from parent")

class Child(Parent):
    def greet(self):
        print("Hello from child")

Predict:

What do you think will be printed?

class Animal:
    def speak(self):
        print("The animal makes a sound")

class Dog(Animal):
    def speak(self):
        print("The dog barks")

dog = Dog()
dog.speak()

Think about:

Both classes define speak()
Which one will Python choose?

Run:

Run the program below to check your prediction.

Why Use super()?

Sometimes you don’t want to completely replace the parent method — you just want to extend it.

This is where super() is used.

super().method_name()

It calls the version of the method from the parent class.

Investigate:

In this example, the child class adds extra behaviour while keeping the parent behaviour.

Try this:

Remove the line with super()
Run the code again
What changes?

Modify:

The following program attempts to extend a parent method but contains an error.

Fix the code so that both messages are printed.

The problem

super() is not being called correctly

Hint:

super().method_name()