with libcomps-0.1.3-1.fc19.x86_64 the following ends up with a SIGEGV on the last line:

#! /usr/bin/python

FN = '/home/akozumpl/tmp/repodata/6cb5995a4849a9bbd94300eae97e6511317cc60222350e511aa660a5922ab292-comps-rawhide.xml'

import dnf.comps

c = dnf.comps.Comps()
c.add_from_xml_filename(FN)
groups = c.groups
env = c.environment_by_pattern('*gnome*')
for grp in groups:
    id_ = grp.id
    print(id_ in env.option_ids)

Please treat this a high-prio as its blocking progress on the DNF Payload for Anaconda.