What are Python decorators?
Python decorators are a significant part of Python programming. In simple terms, a decorator in Python is a function that takes another function as its argument, and extends or modifies the behavior of this input function without explicitly modifying it. They are represented by the @decorator_name in Python and are called in a bottom-up manner. Consider an example of a simple Python function: def simple_function(): print("Hello, World!") Now, suppose we want to extend this function so that it not only prints "Hello, World!", but also tells us the time at which it was printed. One way to do this would be to modify the original function like so: import time def simple_function(): print(time.ctime()) print("Hello, World!") However, modifying the original function is not always desirable or practical, especially if the function is complex or used in multiple places. This is where decorators come into play. Instead of modifying the original function, we can create a decorator that adds the desired functionality: import time def time_decorator(func): def wrapper(): print(time.ctime()) func() return wrapper @time_decorator def simple_function(): print("Hello, World!") In this case, the `@time_decorator` before the `simple_function()` is Python's decorator syntax. By using this syntax, we are wrapping `simple_function()` inside the `wrapper()` function inside `time_decorator()`. This extends `simple_function()` to first print the current time, and then to print "Hello, World!", all without modifying the original `simple_function()`. Python decorators can be a bit tricky to understand at first, especially since they involve some complex concepts like functions as arguments and closure. However, they are a very powerful tool that allows for more readable and maintainable code once you get the hang of it.