'Remove a sub_port.
:param trunk_id: ID of the trunk.
:param port_id: ID of the subport.'

def remove_sub_port(self, trunk_id, port_id):

    sub_port = SubPort(trunk_id, port_id)
    try:
        if sub_port.bridge.exists():
            sub_port.unplug(self.br_int)
        else:
            LOG.debug('Trunk    bridge    with    ID    %s    does    not    exist.', trunk_id)
    except RuntimeError as e:
        raise TrunkManagerError(error=e)
