In this video I show how to restructure the node tree using several node groups. I also added a Chair Number field, an Instanced field, a Instanced from field and a Mirror field and additional nodes in the node tree to enable copying, instancing and mirroring. Finally I added 4 Store Named Variable nodes so Python can access the data that is processed by the Node Tree. This blender file you can find here:
https://drive.google.com/file/d/1Ju3X...
In the next video I will show how Python can access the data.