code: def get_ofport(self, port_name):
          
          ofport_list = self.db_get_val('Interface', port_name, 'ofport')
          assert len(ofport_list) == 1
          return int(ofport_list[0])
docs: Gets the OpenFlow port number.
  
          This method is corresponding to the following ovs-vsctl command::
  
              $ ovs-vsctl get Interface <port> ofport