Dropping Python 2 Support?

[gricey432]

Hey,

I'm just writing up a PR for this repo to propose a new feature.
I've used Python 3 language features, however it looks like the package is documented as supporting Python 2.
Would you require I submit a Python 2 compatible PR or are you open to matching Flask in supporting only 3.6 and newer?

Cheers

[alexprengere]

Changing the compatibility matrix is a breaking change, so we first need to release a new major version documenting that change, with a clear mention of the new Python versions supported. Ideally we should also modernize the code base (f-strings, annotations, ...). I think Python3.6+ would be a good start (so we effectively drop Python 2.7 and 3.5).

Then we can add Python3-only code. If you do not feel up to it, try to update your code to be "hybrid", supporting both Python2 and Python3 versions (I can help with that if you submit the PR).