with open('userdata.txt','r') as f:
        a = f.readlines()
        for i in a:
            i = i.strip('\n')
            # 实现后台静默运行
            chrome_options = webdriver.ChromeOptions()
            chrome_options.add_argument('--headless')
            br = webdriver.Chrome(chrome_options=chrome_options)
            br.get(url=url)