Python Coding challenge - Day 880| What is the output of the following Python Code?

 

Code Explanation:

1. Class Definition

class P:

Defines a class P, which will contain an initializer and a private variable.

2. Constructor of Class P

def __init__(self):

Defines the constructor that runs when a P object is created.

self.__v = 11

Creates a private attribute named __v and sets it to 11.

Because it starts with double underscore, Python name-mangles it to _P__v.

3. Child Class Definition

class Q(P):

Defines class Q that inherits from class P.

So Q objects automatically get all attributes and methods of P.

4. Method in Class Q

def check(self):

Defines a method inside class Q.

return hasattr(self, "__v")

The hasattr function checks whether the object has an attribute named "__v".

But due to name mangling, the actual attribute name in the object is _P__v,

NOT __v.

So this check returns False.

5. Creating an Object

q = Q()

Creates an instance of class Q.

Since Q inherits from P, the constructor of P runs → _P__v is created.

6. Printing the Result

print(q.check())

Calls check(), which checks if the object has an attribute named "__v".

It doesn’t (because it's stored as _P__v).

So it prints:

False

Output:

False

400 Days Python Coding Challenges with Explanation