Python Coding challenge - Day 720| What is the output of the following Python Code?

 

Code Explanation:

1) import weakref

Imports Python’s weakref module.

A weak reference allows referencing an object without increasing its reference count.

That means the object can still be garbage-collected even if a weak reference to it exists.

2) class A: pass

Defines an empty class A.

It doesn’t have any methods or attributes.

3) a = A()

Creates an instance of class A.

Variable a holds a strong reference to this object.

4) r = weakref.ref(a)

Creates a weak reference to the object a.

r is not the object itself, but a callable reference.

To access the object, you must call r().

5) print(r() is a)

Calls r() → returns the actual object being referenced (same as a).

At this point, a still exists, so r() is the same object.

Output: True.

6) del a

Deletes the strong reference a.

Now the object has no strong references.

Since only a weak reference remains, the object becomes eligible for garbage collection.

7) print(r() is None)

Calls r() again.

The object was garbage-collected after del a.

So r() now returns None.

Output: True.

Final Output

True

True

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