Writing a Script to Turn Downloaded Posts into epubs

[beesbeesbees-cmyk]

I am currently in the process of writing a jupyter notebook containing two main scripts. The first takes the path to the json files of the posts (jsonpath), a desired html output folder (htmlpath), and string containing any tags to filter (targetstr) and converts the posts into html files organized by date. The second script stitches the html files into an epub for offline viewing. I'd made this primarily for myself, but I am still fairly amateur at actually coding and manipulating files this way (hence why it's in a jupyter notebook). I know the current iteration can likely be optimized and improved, but it's been some time since I initially wrote it and I am wondering if anyone more experienced might mind reviewing what I have and pointing me in the right direction for efficiency. There are a lot of if-else statements I can't help but think can be done more elegantly, though I'm not certain how.
Tumblr-html-epub-v1-0.zip