PythonMC is a Fabric mod that allows datapacks to be written in Python. Minecraft datapacks have some big limitations but, PythonMC has very little. Like for loops, functions, if statements, and ...

PyPlugins - is a plugins loader for Bukkit/Spigot (PaperMC) to load plugins are written on Python 2.7 (via Jython 2.7.2). Zips with the .pyplugin extension are recommended if you release any plugins.