你这个session没有创建成功
你补全一下:
desired_caps = {}
desired_caps['platformName'] = 'Android' # 设备系统
desired_caps['platformVersion'] = '6.0.1' # 设备系统版本
desired_caps['deviceName'] = '192.168.0.1:5555' # 设备名称
desired_caps['app'] = r"E:\tests\GuoYuB2B_2.1.apk"
desired_caps['appPackage'] = 'xxxxx'
desired_caps['appActivity'] = 'xxxx.activity.SplashActivity'
driver = webdriver.Remote("http://localhost:4723/wd/hub", desired_caps)