Python Coding challenge - Day 591| What is the output of the following Python Code?

 

Code Explanation:

Decorator Function Definition

def dec(f):

    def wrap(x): return f(x) + 1

    return wrap

Explanation:

dec(f) is a decorator that:

Wraps a function f

Calls f(x) and adds 1 to the result

The inner function wrap does the actual wrapping logic.

It returns wrap, effectively replacing the original function.

First Definition of num (Decorated)

@dec

def num(x): return x * 2

Explanation:

This is equivalent to:

def num(x): return x * 2

num = dec(num)  # num now points to wrap(x)

So num(2) at this point would compute:

x * 2 = 4

Then wrap adds 1 → 4 + 1 = 5

Second Definition of num (Overrides the First!)

def num(x): return x * 3

Explanation:

This redefines the num function.

The decorated version (num = dec(...)) is overwritten.

So the decorator is now completely discarded.

Now, num(2) → 2 * 3 = 6

Function Call and Output

print(num(2))

Explanation:

Calls the second version of num (not decorated).

So output is simply:

2 * 3 = 6

Final Output:

6

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