'Return device state attributes.'

@property
def device_state_attributes(self):

    state_attr = {ATTR_TARGET_HEAT: self._usrobj.target_heating_level}
    state_attr[ATTR_ACTIVE_HEAT] = self._usrobj.now_heating
    state_attr[ATTR_DURATION_HEAT] = self._usrobj.heating_remaining
    state_attr[ATTR_LAST_SEEN] = self._usrobj.last_seen
    return state_attr
