Inheritance lets you build new classes on top of existing ones, reusing and extending their behavior.
Work through the concepts using Python in your editor or Replit. Use the knowledge check below to test yourself.
Open a Python file and implement the core concepts from this lesson. Start small, test each part, then combine.
What does inheritance allow?
Inheritance lets a subclass reuse code from a parent class. Memory sharing is a separate concept.
Multiple classes in one file is always allowed. Inheritance is about sharing behavior between parent and child classes.
Instantiation and inheritance are independent features.
What does super().__init__() do?
super().__init__() calls the parent class's __init__ method to initialize the parent's portion of the object.
super() provides a proxy to the parent class so you can call its methods. The parent class still exists.
You import with 'from file import ClassName'. super() is for calling parent class methods.
Polymorphism means:
Polymorphism: different classes implement the same interface/method name and can be used interchangeably.
Polymorphism is about different classes sharing an interface. No limit on methods per class.
Dynamic typing lets variables hold any type. Polymorphism is about objects of different types responding to the same method calls.
What is duck typing?
Duck typing: if it has the method you need, use it. Don't check isinstance() unless necessary.
Abstract classes enforce that subclasses implement certain methods. Duck typing just uses whatever methods are available.
Overriding means replacing a parent method in a subclass. Duck typing is about using objects based on their capabilities, not their type.
What is method overriding?
In Python, defining two methods with the same name in one class means the second replaces the first - not overriding in the OOP sense.
Too many arguments raises TypeError. Overriding means redefining a parent method in a subclass.
Private methods are prefixed with _ or __. Overriding is specifically about subclasses replacing parent methods.