Purpose of polymorphism in Python - Mini Project: Build & Apply

Purpose of polymorphism

📖 Scenario: Imagine you are creating a simple program to handle different types of animals in a zoo. Each animal can make a sound, but the sound is different for each animal. You want to write code that can work with any animal without changing the main program.

🎯 Goal: Build a small Python program that shows how polymorphism allows different animal objects to use the same method name make_sound() but produce different sounds.

📋 What You'll Learn

Create classes for different animals with a method called make_sound()

Use polymorphism to call make_sound() on different animal objects

Print the sounds made by each animal using the same method name

💡 Why This Matters

🌍 Real World

Polymorphism is used in software to handle different types of objects with the same interface, like different payment methods in an online store.

💼 Career

Understanding polymorphism is key for writing flexible and reusable code, a skill important for software developers and engineers.

1

Create animal classes with make_sound() methods

Create two classes called Dog and Cat. Each class should have a method called make_sound(). In Dog, make_sound() should return the string "Woof". In Cat, make_sound() should return the string "Meow".

Python

# Your code here

Need a hint?

Define two classes with the same method name but different return values.

2

Create a list of animal objects

Create a list called animals that contains one Dog object and one Cat object.

Python

class Dog:
    def make_sound(self):
        return "Woof"

class Cat:
    def make_sound(self):
        return "Meow"

# Your code here

Need a hint?

Create a list with one object of each class.

3

Use polymorphism to call make_sound() on each animal

Use a for loop with the variable animal to iterate over the animals list. Inside the loop, call animal.make_sound() and store the result in a variable called sound.

Python

class Dog:
    def make_sound(self):
        return "Woof"

class Cat:
    def make_sound(self):
        return "Meow"

animals = [Dog(), Cat()]

# Your code here

Need a hint?

Loop through each animal and call the same method name.

4

Print the sounds made by each animal

Inside the for loop, add a print() statement to display the value of sound.

Python

class Dog:
    def make_sound(self):
        return "Woof"

class Cat:
    def make_sound(self):
        return "Meow"

animals = [Dog(), Cat()]

for animal in animals:
    sound = animal.make_sound()
    # Your code here

Need a hint?

Print the sound inside the loop to see each animal's sound.