`ap` is a command-line client for the ActivityPub protocol coded in Python by @evan@cosocial.ca, initially developed to illustrate how to write client code for the ActivityPub API as part of his book for O'Reilly Media, "ActivityPub: Programming for the Social Web".

I build a lot of command-line tools in Python. It’s become my favorite way of quickly turning a piece of code into something I can use myself and package up for other people to use too.
[...] Here are some notes on what I’ve learned about designing and implementing CLI tools in Python so far.

It's an interactive Unix filter for command-line that can be used with any list; files, command history, processes, hostnames, bookmarks, git commits, etc.