Pytest setup feasibility pilot

Hi, I run a beginners python course, and when it first started I didn't know about pytest. I wrote an automatic marking system based on a completely homemade testing setup. It works, and it's been just fine for a long time now, but I'd like to explore converting it across to pytest so that others will have an easier time contributing to the code.
The course code is here: https://github.com/design-Computing
The course website is here: https://design-computing.github.io/
and quite detailed instructions on how to set up the course are here: https://design-computing.github.io/md/week1

I'm interested to see if there's an easy way for students, using vs code, to use the testing interface in the UI to test their code.
I'd like to maintain the separation of their-code and course-code, as it is now, because that means that we can update the code during the semester without having to teach them anything too complex.

There are a lot of different things that the system currently tests for. I don't need to know that they can all be done, I just need to be confident that I can keep extending it until it's all in pytest.

I would also be OK with a negative response, i.e. that there's no way to do this.

I suspect that we'd need to talk this through a fair bit more, but this should be enough to give you an idea of what I'm thinking. Let me know your thoughts and we can discuss a more specific scope.