Binary package “python3-six” in ubuntu xenial

Python 2 and 3 compatibility library (Python 3 interface)

 Six is a Python 2 and 3 compatibility library. It provides utility
 functions for smoothing over the differences between the Python versions
 with the goal of writing Python code that is compatible on both Python
 versions.
 .
 This package provides Six on the Python 3 module path. It is complemented
 by python-six and pypy-six.