'Get conj_id specified by the arguments
and notify the manager that
(remote_sg_id, direction, ethertype, conj_id) flows need to be
populated on the vlan_tag network.
A caller must call update_flows_for_vlan to have the change in effect.'

def add(self, vlan_tag, sg_id, remote_sg_id, direction, ethertype):

    conj_id = self.conj_id_map.get_conj_id(sg_id, remote_sg_id, direction, ethertype)
    if ((direction, ethertype) not in self.conj_ids[vlan_tag]):
        self.conj_ids[vlan_tag][(direction, ethertype)] = collections.defaultdict(set)
    self.conj_ids[vlan_tag][(direction, ethertype)][remote_sg_id].add(conj_id)
    return conj_id
