Hiding Your API keys in your code from Thieves

Any ideas on how to do this with a shared notebook? The shared users won't have access to my drive, so this wouldn't work as is. I've scoured the internet, and no one seems to have a solution for how to truly hide keys (or anything) in a shared Google Colab. Kind of a surprising gap, not being able to code modern (everything has an API), secure apps to share! (and my users aren't sophisticated enough to get their own API...I don't mind them using my app with my key, I just don't want anyone to be able to use the key for something else.