docs: def runCommandReturnOutput(cmd):
      """
      Runs a shell command and return the stdout and stderr
      """
      splits = shlex.split(cmd)
      proc = subprocess.Popen(
          splits, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
      stdout, stderr = proc.communicate()
      if proc.returncode != 0:
          raise subprocess.CalledProcessError(stdout, stderr)
      return stdout, stderr