Python Coding Challenge - Question with Answer (ID -191225)

 

What this code is trying to do

• Define a class A

• Create an object obj

• Print the object

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 The Problem in the Code

__init__() is a constructor.
Its job is to initialize the object, not return a value.

👉 Rule:
__init__() must always return None

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 What happens internally

1. Python creates a new object of class A

2. Python calls __init__(self)

3. Your __init__() returns 10

4. Python checks the return value

5. ❌ Python raises an error because returning anything from __init__() is not allowed

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❌ Actual Output (Error)

TypeError: __init__() should return None, not 'int'

⚠️ Because of this error, print(obj) never executes.

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✅ Correct Version

class A:
     def __init__(self):
         self.value = 10 # assign, don’t return

obj = A()
print(obj.value)

Output:

10

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 Key Exam / Interview Point

• __init__()
  ✔ Used for initialization
  ❌ Cannot return values

• Returning anything → TypeError

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