Python 未能捕获特定错误

我编写了以下简单代码：

#!/usr/bin/python2.7 -tt

import subprocess

def main()
  try:
    process = subprocess.check_output(['unvalidcommand'],shell=True)
  except CalledProcessError:
    print 'there is the calledProcessError'


if __name__ == '__main__':
  main() 

预期输出：

存在被调用的进程错误

我得到的信息：

name错误：未定义全局名称“CalledProcessError”

def main():
  try:
    process = subprocess.check_output(['unvalidcommand'],shell=True)
  except subprocess.CalledProcessError: # need to use subprocess.CalledProcessError
    print 'there is the calledProcessError'
main()
there is the calledProcessError
/bin/sh: 1: unvalidcommand: not found

或者只需从

子流程导入所需：

from subprocess import check_output,CalledProcessError

def main():
  try:
    process = check_output(['unvalidcommand'],shell=True)
  except CalledProcessError:
    print 'there is the calledProcessError'
main()

不是一个内置的例外。您需要限定异常名称才能使用它

except subprocess.CalledProcessError:
       ^^^^^^^^^^^

或者您需要显式导入它：

from subprocess import CalledProcessError

应该是
子进程。称为进程错误
。