Python Coding challenge - Day 941| What is the output of the following Python Code?

Code Explanation:

1. Defining the Class

class A:

A class named A is defined.

It customizes attribute access behavior by overriding special methods.

2. Overriding __getattribute__

    def __getattribute__(self, name):

        print("get", name)

        return super().__getattribute__(name)

__getattribute__ is called for every attribute access, even for non-existing ones.

It prints "get <attribute_name>".

Then it delegates the actual lookup to the default implementation using super().

3. Defining __getattr__ as a Fallback

    def __getattr__(self, name):

        return 5

__getattr__ is only called if normal attribute lookup fails.

It returns 5 when an attribute is not found.

4. Creating an Object

print(A().x)

Step-by-step execution:

A() creates an object of class A.

Python evaluates A().x.

Python first calls __getattribute__(self, "x").

Inside __getattribute__, it prints:

get x

Then it calls super().__getattribute__("x").

Since x does not exist, super().__getattribute__ raises AttributeError.

Because __getattribute__ does not catch this error, Python does not fall back to __getattr__.

The program crashes.

5. Why __getattr__ Is Not Used Here

Normally, if attribute lookup fails, Python calls __getattr__.

But in this case:

__getattribute__ is overridden.

It calls super().__getattribute__ which raises AttributeError.

But since the error happens inside __getattribute__ and is not handled, __getattr__ is never triggered.

To allow fallback, you must handle the exception manually.

6. Final Output

get x

Then Python raises:

AttributeError: 'A' object has no attribute 'x'

Final Answer

✔ Output printed:

get x

Then program crashes with:

AttributeError: 'A' object has no attribute 'x'

400 Days Python Coding Challenges with Explanation