Nesting parts, chapters, sections

[msche]

I'm working on a large jupyter book and would like to create some structure within my table of content. I tried to nest Parts so build up the structure but that caused build failures. Is it possible to create a nested structure, and what would be the best practice.

PS: Preferably, I would like to have the nested structure collapsible so that the TOC remains 'small'/overseeable.