I had to install OpenStack using devstack infrastructure for experiements with open vSwitch, and found this in the logs:
/usr/lib/python2.7/site-packages/setuptools/dist.py:298: UserWarning: The version specified ('2014.2.2.dev5.gb329598') is an invalid version, this may not work as expected with newer versions of setuptools, pip, and PyPI. Please see PEP 440 for more details.
I googled and found PEP440, but I wonder how serious is this warning?