How to implement a decorator in Python so that the original function remains accessible for calls?

To keep the original function accessible after applying a decorator, you can save a reference to it as an attribute of the wrapper. Often, functools.wraps is used for this purpose, which copies metadata and preserves a reference to the original in the __wrapped__ attribute.

Example:

import functools

def my_decorator(func):
    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        print("Before calling the function")
        result = func(*args, **kwargs)
        print("After calling the function")
        return result
    return wrapper

@my_decorator
def greet(name):
    print(f"Hello, {name}!")

# Calling the decorated function

greet("World")

# Access to the original function
original = greet.__wrapped__
original("World")

Thus, greet.__wrapped__ is the original function without the decorator.