I've only skimmed the book and even though it was clearly written with the help of AI, there is some very good (and for the Python world novel) stuff in it. I particularly liked the chapter on effects.[0] I very much share the author's opinion that properly managing effects is the future:
> The history of programming is a history of scaling barriers. Each time, the pattern is the same. Something the programmer tracks by hand works fine in small programs. Systems grow until hand-tracking fails. The solution moves that tracking into the language or the toolchain, and a generation later, nobody can imagine doing it by hand. […] Effects are the barrier we are inside right now, which is why it is hard to see.