Python Coding challenge - Day 1038| What is the output of the following Python Code?

 

Code Explanation:

1. Importing Abstract Class Tools

from abc import ABC, abstractmethod

Imports utilities from Python’s abc module

ABC → base class used to create abstract base classes

abstractmethod → decorator to declare mandatory methods

🔹 2. Defining Abstract Base Class A

class A(ABC):

Class A inherits from ABC

This makes A an abstract class

Abstract classes cannot be instantiated

🔹 3. Declaring an Abstract Method

@abstractmethod

def f(self): pass

Declares method f() as abstract

No implementation is provided (pass)

Any subclass of A must implement f()

📌 This enforces a contract:

“Every concrete subclass must define f()”

🔹 4. Defining Subclass B

class B(A):

    pass

B inherits from abstract class A

B does NOT implement the abstract method f

Therefore, B is still an abstract class

📌 Even though B is a subclass, it remains abstract.

🔹 5. Creating an Object of B

B()

Python checks:

Are there any unimplemented abstract methods? → Yes (f)

Instantiation is not allowed

❌ Runtime Error Raised

TypeError: Can't instantiate abstract class B with abstract method f

700 Days Python Coding Challenges with Explanation