Python Coding challenge - Day 997| What is the output of the following Python Code?

 

Code Explanation:

1. Defining the Class

class Action:

A class named Action is defined.

2. Defining the __call__ Method

    def __call__(self):

        return "go"

__call__ makes an object callable like a function.

When an instance is called (obj()), Python executes:

obj.__call__()

At this point:

Action().__call__() → "go"

3. Creating an Instance

a = Action()

An object a of class Action is created.

Since Action defines __call__, a is callable.

4. Overwriting __call__ on the Instance

a.__call__ = "stop"

This creates an instance attribute named __call__.

It shadows the class’s __call__ method.

Now:

a.__call__ == "stop"

 Important:

Instance attributes take priority over class attributes during lookup.

5. Trying to Call the Object

print(a())

Step-by-step:

Python translates a() into:

a.__call__()

Python looks for __call__ on the instance.

Finds "stop" (a string, not a function).

Tries to execute "stop"().

6. Error Occurs

A string is not callable.

Python raises a TypeError.

7. Final Result (Error)

TypeError: 'str' object is not callable

Final Answer

Output:

TypeError: 'str' object is not callable

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