当出现如下错吴时：
下载一下python语言，点击Scripts
观察是否有：pip.exe（注意图标，自能是这个）
在路径中输入cmd后运行
打开后输入：pip install appium-python-client 就可以了
- unsupported Unknown command install 39unsupported unknown command install macosversionerror unsupported unknown version 39 unsupported typeerror str 39 type unsupported typeerror redisson unknown command问题 npm err install unknown installed command whether script node-sass install command failed install command linux login seqeval install 39 evaluate-metric