Python by Examples: Abstract Base Classes and Interfaces

Abstract Base Classes (ABCs) and interfaces in Python provide a way to define a common interface for a group of related classes. They help in ensuring that certain methods are implemented in the derived classes, promoting a consistent API and supporting polymorphism. Python’s `abc` module is the tool that enables developers to create these abstract classes.

What is Abstract Base Class in Python?

An Abstract Base Class is a class that cannot be instantiated, and it typically includes one or more abstract methods that must be implemented by any subclass. In Python, the `abc` module provides the `ABC` meta-class and the `abstractmethod` decorator to facilitate this.

Why using abstract class in Python?

First, abstract class brings code consistency. It enforces a consistent interface, making it easier for developers to understand and use multiple implementations.

Second, abstract class helps to reduce bugs. It guarantees that subclasses implement necessary methods, reducing the likelihood of run-time errors.

Third, abstract class brings polymorphism to Python. It allows functions to operate on objects of different classes as long as they adhere to a particular interface.