See https://80by24.net and the READMEs for client and server.
The directory structure for this repo is a little elaborate.
The client, server and common files each have the structure of a standard Python distribution. Their top-level names
run80by24-client, run80by24-server and run80by24-common correspond to the names under which they are known by pip.
Within these, the source files reside under a namespace directory run80by24 and subpackage directory client,
server or common.
So, the client source is at run80by24-client/run80by24/client/__main__.py