Refactor cut and retain git blame history

[desh2608]

This should hopefully retain all (most?) of the git blame history. The trick is to create a new branch for each split file, and create the new file using git mv so that it retains the history of the original file. Once all the branches are created, we merge them together.

[pzelasko]

Thanks, amazing work! Please fix the failing style check and LGTM

[desh2608]

Thanks, amazing work! Please fix the failing style check and LGTM

I think adding the imports required to resolve the failing checks would cause a circular dependency. See the dependency graph in __init__.py. I am not sure what's a good way to resolve this.

Update: Ideally, making the type hints as strings ("MonoCut" instead of MonoCut), i.e., what is called a forward reference should have been enough, but I don't know why flake8 is still not happy with it. One way to ignore the specific lines is to add a # noqa: F821 on the lines to ignore it.

[pzelasko]

IMO the easiest way to fix is to change the types from specific (like MixedCut) to generic (like Cut). It's still truthful even if it misses on some auto-hint capabilities if we know that there will be only a specific type returned. I think maybe this problem can be fixed on a higher level by adopting typing stub files (.pyi) but that's probably a considerably larger effort.

[desh2608]

Okay, I changed the MonoCut and MixedCut types to Cut. There were still 2 instances of CutSet so I add noqa to ignore them.

[desh2608]

It seems the git history was not retained. If this is an issue, we can revert this merge and try to figure out how to do it.

[pzelasko]

Don't worry about it. I probably messed up because I squashed then merged.