In this chapter, we learned about how the skills that we covered in earlier parts of this book are applied in practice. We did this by stepping through a recording of your humble author's actual process in writing a package. At the same time, you had the chance to work through your own project, make your own decisions, and design your own tests. You've taken the lead in a test-driven project, and you should be able to do it again whenever you want.
Now that we've covered the heart of Python testing, we're ready to talk about testing at the integration and system levels, which we'll do in the next chapter.