def store_a_value(self, tag, value):
		try:
			config = json.loads(value)
			id = self.getLastKey()+1
			id_driver = str(config["id_con"])
			id_vehicle = str(config["id_veh"])
			id_dispatcher = str(config["id_des"])
			id_gasStation = str(config["id_gas"])
			gas = str(config["litros"])
			total = str(config["total"])
			date = time.strftime("%d/%m/%Y")
			code = str(id) + id_driver + id_vehicle + id_dispatcher + id_gasStation
			entry = Invoice(id = id, id_driver = id_driver, id_vehicle = id_vehicle, id_dispatcher = id_dispatcher, id_gasStation = id_gasStation, code = code, date = date, gas=gas, total = total)
			entry.put()
			value = code
		except:
			value = "Error:"+value
		
		if self.request.get('fmt') == "html":
			json.dump({"result": True, "message": value}, self.response.out)
		else:
			self.WriteToPhoneAfterStore(self,tag,value)