Similar question to the other one at the time of writing, but more specific: does anyone have a good, thorough introduction to the "async event loop" (sometimes

Similar question to the other one at the time of writing, but more specific: does anyone have a good, thorough introduction to the "async event loop" (sometimes known as "asyncio") pattern? By thorough I mean that it goes beyond a starter tutorial, into both examples of various supporting libraries and implementation details that matter for usage. I'm fine with a book, too. There are popular libraries for it in both Python and Perl and I suspect I could make good use for it if I understood it. Unfortunately, I've only ever used it in a cargo cult manner of sticking together functions until the error messages go away (yeah yeah, it was only for "throwaway" "prototypes") so I really don't understand how it all is meant to fit together.