Improve tooling #40
Description
This project looks really interesting. I think having a bit more tooling around it would make it easier for others to contribute. Some suggestions that you could consider:
Auto-formatter
Having an auto-formatter installed will make the code more uniform and reduce diffs that are just due to formatting.
I personally would recommend using black, as it has (almost) no configuration options, so will behave the same on each machine and avoid discussions about code-formatting.
Tests
Refactoring parts of the project is a bit risky right now, because there are no automated tests. Making a more clear separation between frontend and backend code and covering at least the latter with automated tests would make refactoring easier.
I personally would recommend to use pytest, as it has an intuitive and easy to understand fixture support.
Linter
You also may want to consider setting up pylint to catch issues in the code that may lead to bugs. Especially because there are no tests right now, I feel that'd be helpful and relatively easy to set up.
A further step could be type-checking using mypy, which would come in handy with refactoring like in #23.