WebUI自动化测试-监听元素有无变化

from datetime import datetime,timedelta
from selenium.webdriver.common.by import By

def get_inocSum(self):
    data = self.findElement(By.ID,'').text
    start_time = datetime.now()
    while True:
        new_data = self.findElement(By.ID,'').text
        if new_data == data:
            if datetime.now() - start_time > timedelta(seconds=3):
                print("接口响应异常，响应时间＞3秒")
                break
        else:
            data = new_data
            break
    return data