Python Coding challenge - Day 964| What is the output of the following Python Code?

 Code Explanation:

1. Defining a Custom Metaclass

class Switch(type):

Switch 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):

        if name == "Worker":

            bases = (str,)

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

__new__ is called whenever a class using this metaclass is created.

Parameters:

cls → the metaclass (Switch)

name → class name being created

bases → original base classes

dct → class attributes

What it does:

If the class name is "Worker", it replaces its base class with str.

Otherwise, it leaves bases unchanged.

3. Defining the Base Class

class BaseModel: 

    pass

A normal base class with no behavior.

4. Defining Class Worker

class Worker(BaseModel, metaclass=Switch): 

    pass

Step-by-step:

Python prepares to create Worker.

It calls:

Switch.__new__(Switch, "Worker", (BaseModel,), {...})

Inside __new__:

name == "Worker" → True

bases is replaced with (str,)

So Worker is actually created as:

class Worker(str): pass

Not as Worker(BaseModel).

5. Printing the Base Classes

print(Worker.__bases__)

Shows the actual base classes of Worker.

Since the metaclass changed it, the base is str.

6. Final Output

(<class 'str'>,)

Final Answer

✔ Output:

(<class 'str'>,)

100 Python Programs for Beginner with explanation