What is the decorator in python

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Decorators

Decorators give us an efficient way to add functionality to existing functions or classes. Does that sound like Aspect-Oriented Programming in Java? Both are simple, and decorators have more powerful features. For example, suppose you want to do something special at the entry and exit points of a function (security, tracking, locking, etc.).

A decorator is a special function wrapped around another function: the main function is called and its return value is passed to the decorator, which then returns a substitute function wrapped around the main function, which the rest of the program will see as the wrapper function.

import timefrom functools import wrapsdef timethis(func): ''' Decorator that reports the execution time. ''' @wraps(func) def wrapper(*args, **kwargs): start = time.time() result = func(*args, **kwargs) end = time.time() print(func.__ name__, end-start) return result return wrapper@timethisdef countdown(n): while n > 0: n -= 1countdown(100000)#('countdown ', 0.00699969482421875) Thank you for reading! About "python decorator is what" this article is shared here, I hope the above content can have some help to everyone, so that everyone can learn more knowledge, if you think the article is good, you can share it to let more people see it!