This chapter showed us how to create generators and both the strengths and weaknesses that they possess. Additionally, it should now be clear how to work around their limitations and the implications of doing so.

While the paragraphs about coroutines should have provided some insights into what they are and how they can be used, not everything has been shown yet. We saw the constructs of both pure coroutines and coroutines that are generators at the same time, but they are still all synchronous. The coroutines allow sending the results to many other coroutines, therefore effectively executing many functions at once, but they can still freeze Python completely if an operation turns out to be blocking. That's where our next chapter will help.

Python 3.5 introduced a few useful features, such as the async and await statements. These make it possible to make coroutines fully asynchronous and non-blocking, whereas this chapter uses the basic coroutine features that have been available since Python 2.5.

The next chapter will expand on the newer features, including the asyncio module. This module makes it almost simple to use coroutines for asynchronous I/O to endpoints such as TCP, UDP, files, and processes.