Honestly, there's a lot of moving parts here that can get confusing quickly, especially for inexperienced Python programmers. A lot of practice and documentation referencing is required to get a handle on both decorators and the decorator module.

Do you have to use decorators? No. They are just designed to make the life of a programmer easier. Plus, you should know about them because a lot of third-party libraries and packages, particularly web and GUI frameworks, utilize them.

Once you get a handle on decorators in general, the decorator module will probably make more sense, as well as show itself to be useful in minimizing hand-coded decorators. There is a lot of functionality included in the module that this book doesn't cover, such as converting a caller function directly into a decorator, class decorators, and dealing with blocking calls, that is, a process that won't allow the program to continue until the process is resolved.