Have you tried looking at docopt?

There are cases where it is not flexible enough but it is good for quick and dirty little scripts because:

* you use the docstring to generate the args. This way you always have a minimum usage that is valid

* Argument parsing is a bit more limited than doimg it yourself, but everything you usually need is there

* Docopt is exists not only for Python, but many other languages implemented it too.

Perl has the problem of too many ways to do it. I like MooX::Options. Example here: https://metacpan.org/source/GETTY/AquariumHive-0.003/lib/App...

Installed by default I cannot find any. But pretty much any language with a package manager has sane and easy to use libraries to bang out a small CLI app with subcommands and option parsing in minutes. For example PicoCli in Java, Thor in Ruby and Clap in Rust.

Clojure.