In order to use McThings you need Minecraft or Minetest running with Python support (Raspberry PI Minecraft). Once you have it you can start executing Python code using McThings to build the scenes in Minecraft/Minetest.
Jupyter Notebooks are great to start doing it, and the scenes repository uses this option.
But you can use also other Python environments like PyCharm.
This is a research of the current options to use Python in Minecraft and Minetest.
The options tested are:
This option works with the latest release of Minecraft at this moment: 1.15.2. Install in the Spigot server this plugin and that's all.
In this case you don't need to run a server. Just start the Minecraft Forge client with this plugin installed and in Single Player mode. Tested with the version 1.12.2. The plugin does not work with newer versions. Install process
Probably the Forge server option will work also.
For using Minetest, just install this plugin. Minetest 5.1 has been tested but probably it will work with newer versions. Install process