code: def set_value(self, value, status=NOMINAL, timestamp=None,
                    major=DEFAULT_KATCP_MAJOR):
          
          self._kattype.check(value, major)
          if timestamp is None:
              timestamp = time.time()
          self.set(timestamp, status, value)
docs: Check and then set the value of the sensor.
  
          Parameters
          ----------
          value : object
              Value of the appropriate type for the sensor.
          status : Sensor status constant
              Whether the value represents an error condition or not.
          timestamp : float in seconds or None
              The time at which the sensor value was determined.
              Uses current time if None.
          major : int
              Major version of KATCP to use when interpreting types.
              Defaults to latest implemented KATCP version.