Python Coding challenge - Day 1016| What is the output of the following Python Code?

 

Code Explanation:

1. Defining the descriptor class

class D:

This defines a class named D.

Objects of this class will act as descriptors.

2. Implementing __get__

    def __get__(self, obj, owner):

        return "desc"

__get__ makes D a descriptor.

Parameters:

self → the descriptor object (D()).

obj → the instance accessing the attribute (c).

owner → the class (C).

Whenever this descriptor is accessed, it returns the string "desc".

Since only __get__ is defined, this is a non-data descriptor.

3. Defining the owner class

class C:

This defines a class named C.

4. Assigning the descriptor to a class attribute

    x = D()

x is a class attribute.

It is controlled by the descriptor D.

5. Creating an instance

c = C()

An object c of class C is created.

At this point, c has no instance attributes.

6. Manually adding an instance attribute

c.__dict__['x'] = "inst"

This inserts an instance attribute named x with value "inst".

It directly modifies the instance’s attribute dictionary.

7. Accessing the attribute

print(c.x)

🔍 Attribute lookup order in this case:

Data descriptors

Instance attributes

Non-data descriptors

Class attributes

D is a non-data descriptor.

Python finds x in c.__dict__ first.

The descriptor’s __get__ method is not called.

✅ Final Output

inst

700 Days Python Coding Challenges with Explanation