Show HN: A sum-type decorator for python

I wrote this quick decorator for sum-types and was looking for feedback on if it makes sense. I had to do something similar for work with weird looking if-else blocks with type checks.

I'm also looking for pointers to existing libs that add this and other FP features to python. Comments on the state of FP-like python at work are welcome!

https://github.com/stangirala/python-sumtype-decorator