It's a Python introductory book by RealPython team for people who are unfamiliar with computer science. To its credit, it covers some best practice when it comes to programming. But it's debatable how the chapters are arranged. Especially or the last specific passages about applications, it is extremely interminable and only a scratch of the surface. So I eventually skip some of them. Personally, I have a cloud of suspicion about whether they are added to extend pages by design.