We do something similar for our teaching materials. All lessons are in Jupyter notebooks, as well as cells with inline unit tests, marked with the special comment `# HIDE CELL`.

A build script then runs the full notebook along with tests, and strips out cells (or pieces of a cell) which contain these magic comments.

Admittedly this only captures a piece of what's discussed in the article. Perhaps in the future will construct our videos directly from the notebooks as well, with other special comments containing the relevant pieces of script as well as where the camera should be centered. Then we can generate the notebooks and the visuals automatically, and just send an email to the voiceover person to re-record any script changes.

Very nice ideas in this article, thanks!