Why does the argument of a decorator function not get cleared after execution?

In Python, the argument of a decorator function is not cleared after execution because it is stored in a closure or in the decorator object if the decorator is implemented as a class.

When you write a decorator, it usually takes a function as an argument and returns a new wrapper function. The argument (original function) is stored inside the wrapper so it can be called later. This means that a reference to the argument is kept in memory, and it is not deleted immediately after execution.

Example:

def decorator(func):
    def wrapper(*args, **kwargs):
        print("Before calling the function")
        result = func(*args, **kwargs)  # func is stored in the closure
        print("After calling the function")
        return result
    return wrapper

@decorator
def say_hello():
    print("Hello")

say_hello()

Here, func is the argument of the decorator, which is stored inside wrapper. It is not cleared because wrapper continues to reference func.

Thus, the argument is not cleared after execution so that the wrapper can correctly call the original function on each call.