appium 运行时报错；An unknown server-side error occurred while processing the command. Original error: Una

1、An unknown server-side error occurred while processing the command. Original error: Unable to find an active device or emulator with OS 5.1.1. The following are available: 127.0.0.1:62001 (4.4.2)

处理命令时发生未知的服务器端错误。原始错误：无法找到带有OS 5.1.1的活动设备或仿真器。以下是：127.0.0.1:62001（4.4.2）

怎么解决？

2、UIAutomation2 is only supported since Android 5.0 (Lollipop). You could still use other supported backends in order to automate older Android versions.

UiAutoMe2仅支持Android 5（Lollipop）。您仍然可以使用其他支持的后端来自动化旧的Android版本。

3、解决'python -m pip install --upgrade pip' 报错问题 

     直接在install 后面加一个--user就可以了