I recommend acme-tiny:
https://github.com/Tronde/acme-tiny
It's an acme client in a single, small, stand-alone Python file.
I reverse-engineered it and ported it to Common Lisp. I haven't published the result, but I'd be happy to do so if anyone is interested.
Recommendation from me as well. Have been using this script for multiple years now without a single issue. The minimal code is awesome for avoiding unnecessary external dependencies and complexity.
Be sure to use the latest version from https://github.com/diafygi/acme-tiny though :-)