Hello!
Although we don't cover unit testing specifically in this course (we've got other courses for that!), we've written a blog post on this that you may find interesting.
Specifically this post is about unit testing a simple function that reverses a list.
This is the blog post where we create the function.
And this is the post where we cover unit testing for that function.
I'd suggest reading them in that order so everything's clear!
Happy coding!
Kind regards,
Jose—your instructor