'Excludes all subnets associated with segments
For the case where the host is not known, we don\'t consider any subnets
that are on segments. But, we still consider subnets that are not
associated with any segment (i.e. for non-routed networks).'

@staticmethod
def _query_exclude_subnets_on_segments(query):

    return query.filter(models_v2.Subnet.segment_id.is_(None))
