webargs is a Python library for parsing and validating HTTP request objects, with built-in support for popular web frameworks, including Flask, Django, Bottle
purl - A simple Python URL class
A simple, immutable URL class with a clean API for interrogation and manipulation. Supports Pythons 2.7, 3.3, 3.4, 3.5, 3.6 and pypy.
Also supports template URLs as per RFC 6570