refactor

[H2148]

Overall really good, you've got all the right stuff going on! I like the debug stuff too, use of dictionaries also neat 👍

Here's a few things I would change; it is of course personal though, and there are probably 10 different ways to do this

Some of my reasoning behind the changes

• use more explicit names for stuff (for your own sanity when you look at it after some time has passed, or even just to save brain power)
• refactor code out into separate functions, especially when there are multiple things going on
• try to get functions doing one thing only; it's tricky though, what that one thing is, can be hard to define. I generally think it is a "code smell" if a function is more than 10 lines (depends a bit on the language) and/or multiple loops (especially nested ones) and/or code that is like "if this, then that, but it could be this in which case do the other thing, and then finally"
• no need for comments, it can help force yourself into write the code in an understandable way, i.e, "if skip_download(filepath): continue", "for category in categories".

Code might not actually be working too, I didn't run it : p