为什么 python 不读取环境变量并且无法运行 windows 命令行？

Question

I am trying to run the appium server from my python 3.7 code. So I use this simple line of code:

os.system("start /B start cmd.exe @cmd /k appium")

I see the command windows pop up and give the error "appium' is not recognized as an internal or external command, operable program or batch file".

But I checked my environment variable and they are fine. I can even run appium from command by hand from same folder. Please check the screenshot as a prove:

So what I am doing wrong? Doesn't anyone can help me please?

Answer 1

After some investigation, this is the command which fix my issue:

proc = subprocess.Popen('npm install -g appium',shell=True,stdin=None, stdout=True, stderr=None, close_fds=True)