What environment or setup should I use to facilitate Mathics3-notebook-frontends code development?

[rocky]

I'd like to investigate enhancing code in https://github.com/Mathics3/Mathics3-notebook-frontends/tree/master/mathics3_kernel/frontend

What is a good way to set up a development environment so that I can make changes and rapidly see those changes?

To give some idea of what I am used to, in the Django project, the Mathics Kernel code points to the github branch that I currently have checked out (which I installed initially using pip install -e .).

So how do I set things up so this kind of thing happens in environment that is most favorable for doing this? (Down the line, I'd be interested in all environments, but I am okay with starting out with just one.)

Furthermore, Django has this feature that it is watching all of the Python files for the modules it has loaded. If any of the files changes, then the server is restarted. How would I do something like this for one of the notebook environments?

If there is information already written that suggest how to develop packages like this in Jupyter let me know and I will read those and try to follow this.