'Make a CG representation compatible with a target version.'

def obj_make_compatible(self, primitive, target_version):

    super(ConsistencyGroup, self).obj_make_compatible(primitive, target_version)
    target_version = versionutils.convert_version_to_tuple(target_version)
    if (target_version < (1, 3)):
        for obj_field in ('cluster', 'cluster_name'):
            primitive.pop(obj_field, None)
