Decorators in Python are a prime-time example of a perfectly implemented feature. It does take a while to wrap your head around, ... The ABC of Python decorators. Functions with an @ symbol.

$ python decorator_test.py Function calculate_squares being called at 2018-08-23 12:39:02.112904 Took 2.5019338130950928 seconds ... in your first decorator example print_phrase() ...

Python decorator is a feature that is used to enhance the functionality of an existing function or a class. It is preferred when a developer wants to dynamically update the working of a function ...