'Set operation mode (auto, cool, heat, off).'

def set_operation_mode(self, operation_mode):

    if (operation_mode == STATE_OFF):
        self.device.tmode = 0
    elif (operation_mode == STATE_AUTO):
        self.device.tmode = 3
    elif (operation_mode == STATE_COOL):
        self.device.t_cool = (round((self._target_temperature * 2.0)) / 2.0)
    elif (operation_mode == STATE_HEAT):
        self.device.t_heat = (round((self._target_temperature * 2.0)) / 2.0)
