Python Coding challenge - Day 942| What is the output of the following Python Code?

 

Code Explanation:

1. Defining a Custom Metaclass

class Meta(type):

Meta is a metaclass because it inherits from type.

A metaclass controls how classes are created.

2. Overriding the Metaclass __new__ Method

    def __new__(cls, name, bases, dct):

        dct["x"] = 10

        return super().__new__(cls, name, bases, dct)

This method runs when a class is being created.

Parameters:

cls → the metaclass (Meta)

name → name of the class being created ("A")

bases → parent classes

dct → dictionary of attributes defined inside the class

What it does:

Adds a new class attribute x = 10 into the class dictionary.

Then calls type.__new__ to create the actual class.

So every class created with this metaclass automatically gets x = 10.

3. Creating Class A Using the Metaclass

class A(metaclass=Meta):

    pass

What happens internally:

Python sees metaclass=Meta.

Calls:

Meta.__new__(Meta, "A", (), {})

Inside __new__, x = 10 is injected.

Class A is created with attribute x.

So effectively, Python turns it into:

class A:

    x = 10

4. Accessing the Injected Attribute

print(A.x)

A.x looks for attribute x in class A.

It finds x = 10 (injected by the metaclass).

Prints 10.

5. Final Output

10

Final Answer

✔ Output:

10

900 Days Python Coding Challenges with Explanation