The super() Function

Part of the Object Oriented Programming section of Coddy's Python journey — lesson 18 of 64.

The super() function allows a child class to call methods from its parent class. This lets you extend parent functionality rather than completely replace it.

Here is an example of using super() in the constructor:

class Animal:
    def __init__(self, name):
        self.name = name
        print(f"Animal created: {name}")

class Dog(Animal):
    def __init__(self, name, breed):
        super().__init__(name)  # Call parent's __init__
        self.breed = breed
        print(f"Dog breed set: {breed}")

Create a dog object:

buddy = Dog("Buddy", "Golden Retriever")
print(f"Name: {buddy.name}, Breed: {buddy.breed}")

Output:

Animal created: Buddy
Dog breed set: Golden Retriever
Name: Buddy, Breed: Golden Retriever

Use super() to extend parent methods:

class Animal:
    def make_sound(self):
        print("Generic animal sound")

class Dog(Animal):
    def make_sound(self):
        super().make_sound()  # Call parent's method first
        print("Woof!")        # Add dog-specific behavior

Call the extended method:

buddy = Dog()
buddy.make_sound()

Output:

Generic animal sound
Woof!

Without super(), you would lose the parent's functionality:

class Cat(Animal):
    def make_sound(self):
        print("Meow!")  # Only cat sound, parent method ignored

cat = Cat()
cat.make_sound()

Output:

Meow!

Key Point: Use super() to call parent class methods from child classes. This allows you to extend functionality rather than completely replace it. Common uses include calling parent __init__ methods and extending parent behavior.

Challenge

Medium

In this challenge, you'll implement a Person and Employee class hierarchy using inheritance.

person.py: Contains the Person class with name and age attributes
employee.py: Contains the Employee class that inherits from Person
driver.py: Main file to test your implementation

Each file contains detailed TODO comments to guide you through the implementation.

Cheat sheet

The super() function allows a child class to call methods from its parent class, extending functionality rather than replacing it.

Using super() in constructors:

class Animal:
    def __init__(self, name):
        self.name = name

class Dog(Animal):
    def __init__(self, name, breed):
        super().__init__(name)  # Call parent's __init__
        self.breed = breed

Using super() to extend methods:

class Animal:
    def make_sound(self):
        print("Generic animal sound")

class Dog(Animal):
    def make_sound(self):
        super().make_sound()  # Call parent's method first
        print("Woof!")        # Add child-specific behavior

Without super(): Child methods completely replace parent functionality instead of extending it.

Try it yourself

# TODO: Import the Person class from person.py
# TODO: Import the Employee class from employee.py

def main():
    # TODO: Create a Person object with name "Alice" and age 30
    person = None
    
    # TODO: Create an Employee object with name "Bob", age 35, and job "Developer"
    employee = None
    
    # TODO: Call the introduce() method on the Person object
    # Expected output: "Hi, I'm Alice and I'm 30 years old"
    
    # TODO: Print a blank line for spacing - print()
    
    # TODO: Call the introduce() method on the Employee object
    # Expected output: 
    # "Hi, I'm Bob and I'm 35 years old"
    # "I work as a Developer"

if __name__ == "__main__":
    main()