'Return the state attributes.'

@property
def device_state_attributes(self):

    result = {}
    if ((self._sensor_type == SENSOR_TEMPERATURE) and (self._ppm is not None)):
        result[ATTR_CO2_CONCENTRATION] = self._ppm
    if ((self._sensor_type == SENSOR_CO2) and (self._temperature is not None)):
        result[ATTR_TEMPERATURE] = self._temperature
    return result
