After the release of Dateutil 2.5 I am seeing a number of Deprecation warnings when running the test suite:

It's not a big issue at the moment but we should preferably fix this before 2.0 so we remain compatible with future versions of Dateutil.

/Users/jhn/Envs/mplmaster/lib/python3.5/site-packages/dateutil/rrule.py:415: DeprecationWarning: Using both 'count' and 'until' is inconsistent with RFC 2445 and has been deprecated in dateutil. Future versions will raise an error.