Python Coding challenge - Day 585| What is the output of the following Python Code?

 

Code Explanation:

 1. Define a Decorator Function

def decorator(f):

    def wrapper(x):

        return f(x) + 1

    return wrapper

decorator is a higher-order function: it takes a function f as input.

Inside it, wrapper(x) is defined, which:

Calls the original function f(x).

Adds 1 to the result.

wrapper is returned — this becomes the new version of the function.

2. Apply Decorator Using @ Syntax

@decorator

def f(x):

    return x * 2

This is syntactic sugar for:

def f(x):

    return x * 2

f = decorator(f)  # f now refers to wrapper(x)

So f is now replaced by wrapper(x).

3. Call the Decorated Function

print(f(3))

Since f is now wrapper, here's what happens:

wrapper(3) is called.

Inside wrapper:

f(3) is evaluated as 3 * 2 = 6.

6 + 1 = 7 is returned.

Final Output

7

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