capabilities are required, but were not provided: platformName, deviceName)

问题遇到的现象和发生背景

用代码块功能插入代码，请勿粘贴截图

from appium import webdriver
import time

desired_cap = {}
desired_cap["platformName"] = "Android"
desired_cap["platformVersion"] = "9.0"
desired_cap["deviceName"] = "emulator-5554"
desired_cap["appPackage"] = "com.android.launcher3"
desired_cap["appActivity"] = "com.android.launcher3.Launcher"
desired_cap['automationName'] = 'Viautomator2'
desired_cap['noReset'] = True
desired_cap['newCommandTimeout'] = 6000
desired_cap['unicodeKeyboard'] = True
desired_cap['resetKeyboard'] = True
print(desired_cap)

driver = webdriver.Remote('http://localhost:4723/wd/hub', desired_cap)

运行结果及报错内容