code: def rate_sp(self):
          
          self._rate_sp, value = self.get_attr_int(self._rate_sp, 'rate_sp')
          return value
docs: Sets the rate_sp at which the servo travels from 0 to 100.0% (half of the full
          range of the servo). Units are in milliseconds. Example: Setting the rate_sp
          to 1000 means that it will take a 180 degree servo 2 second to move from 0
          to 180 degrees. Note: Some servo controllers may not support this in which
          case reading and writing will fail with `-EOPNOTSUPP`. In continuous rotation
          servos, this value will affect the rate_sp at which the speed ramps up or down.