This repo has code that builds a simple web app and allows end-users to provide a prompt that then is used by GPT2 to generate an output.
In general, this is quite slow on my machine as I have my GPU disabled. This is a good example repo for me in case I want to build similar transformer based apps in future. It uses rust-bert as the core of NLP models and you can swap out bits for other bits and build a more fun set of examples.