It's just awkwardly worded, I think. It probably should include a mention of ProcessPoolExecutor in the following bit where it explains the run_in_executor func

It's just awkwardly worded, I think. It probably should include a mention of ProcessPoolExecutor in the following bit where it explains the run_in_executor function to make more sense. Especially as the whole section talks about passing CPU-bound task to a thread pool, but then recommends not to use a thread pool. Though I think the GIL isn't really that big a deal for most CPU-bound code, with plenty of third party libraries and even within the python standard library a lot of the code is not native python, and therefore releases the GIL lock.