Haha, please don't get me wrong! I didn't mean to say that concurrency in python is any easier - it's probably even harder than in shell.

> Regarding your "complicated" use cases, I must confess that I don't understand them nor their relevance.

They are two recent examples of mine. But even if you don't see the relevance in them: if shell truly makes concurrency trivial, then the shell code should not look much more difficult then my English descriptions.