Python Coding challenge - Day 982| What is the output of the following Python Code?

 

Code Explanatiion:

1. Defining a Metaclass Meta

class Meta(type):

Meta is a metaclass.

A metaclass is a class that creates other classes.

Here, Meta inherits from type, which is the default metaclass in Python.

2. Overriding the __new__ Method of the Metaclass

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

__new__ is called when a new class is being created

Parameters:

cls → the metaclass (Meta)

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

bases → base classes of A (here, (object,))

dct → dictionary containing class attributes and methods

3. Adding a Class Attribute Inside __new__

        dct["version"] = 1

A new entry version is added to the class dictionary.

This means every class created using Meta will have version = 1.

4. Creating the Class Object Using type.__new__

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

Calls the parent metaclass (type) to actually create the class.

Returns the newly created class object.

5. Defining Class A Using the Metaclass

class A(metaclass=Meta):

    pass

Class A is created using the metaclass Meta.

pass means no attributes or methods are explicitly defined in A.

During class creation:

Meta.__new__ is executed

version = 1 is injected into A

So internally, A becomes:

class A:

    version = 1

6. Accessing the Class Attribute

print(A.version)

version is a class attribute, not an instance attribute.

It was added automatically by the metaclass.

Python finds version in A and prints its value.

7. Final Output

1

700 Days Python Coding Challenges with Explanation