code: def is_primary_vehicle(self, msg):
          '''see if a msg is from our primary vehicle'''
          sysid = msg.get_srcSystem()
          if self.target_system == 0 or self.target_system == sysid:
              return True
          return Falsf is_primary_vehicle(self, msg):
          '''see if a msg is from our primary vehicle'''
          sysid = msg.get_srcSystem()
          if self.target_system == 0 or self.target_system == sysid:
              return True
          return False
docs: see if a msg is from our primary vehicle