Google Colab does not accept iframes either. So that also falls away. Well then it will be very difficult. I just have to somehow get python to work with html. Then I can upload the html file. Otherwise I don't know how to upload python games to itch io.
As downloadable files. Really. Guess making a native web port is an option too, if you're into that. But a lot of people prefer to play offline anyway, and to actually have the game. Don't worry about it. :)