Consider using Flask Configuration Handling

[tschaffter]

https://flask.palletsprojects.com/en/1.1.x/config/

[tschaffter]

@thomasyu888 Here is how we handle the data node configuration. Could you tell me what you think of this implementation?

[thomasyu888]

@tschaffter , I don't think theres anything particularly wrong with the way we are doing it. That being said, it may be nicer to use an already available tool to handle the data node creation instead of relying on custom code.

I took a look, and it seems like config.py is something you wrote - not autogenerated. I don't have a strong preference, this seems like a "nice to have", but isn't a blocker.