Read the OpenStack Style Commandments https://docs.openstack.org/hacking/latest/
[V316] assertTrue(isinstance(a, b)) sentences not allowed [V317] assertEqual(type(A), B) sentences not allowed [V318] assertEqual(A, None) or assertEqual(None, A) sentences not allowed [V319] Don't translate logs [V321] contextlib.nested is deprecated [V322] use a dict comprehension instead of a dict constructor with a sequence of key-value pairs [V323] Do not use xrange. Use range, or six.moves.range [V324] Use six.iteritems() or dict.items() instead of dict.iteritems() [V325] Use six.iterkeys() or dict.keys() instead of dict.iterkeys() [V326] Use six.itervalues() or dict.values instead of dict.itervalues() [V327] Method's default argument shouldn't be mutable [V328] Disallow LOG.warn [V329] Don't use assertEqual(True/False, observed).