Thanks for the nice tutorial OP.

Here's a public notebook in Deepnote if anyone wants to play around with the code or duplicate it: https://deepnote.com/project/Converting-Markdown-to-Epub-or-...

2 fun facts about Deepnote:

1. You can create a Custom environment by writing a Dockerfile with all the libraries you need to install and everytime you're in a need to re-use a similar functionality (e.g. convert yet another book to mobi), you can just fire it up and all will be preinstalled. https://docs.deepnote.com/environment/custom-environments

2. You can turn any notebook to a blogpost right away and publish within Deepnote directly.

Disclaimer: I'm a software engineer at Deepnote.