Klein is a micro-framework for developing production-ready web
services with Python. It is 'micro' in that it has an incredibly
small API similar to Bottle and Flask. It is not 'micro' in that
it depends on things outside the standard library. This is primarily
because it is built on widely used and well tested components like
Werkzeug and Twisted.

Homepage:
https://klein.readthedocs.io/en/latest/
