code: def create_process(cmd, root_helper=None, addl_env=None, log_output=True):
      
      if root_helper:
          cmd = shlex.split(root_helper) + cmd
      cmd = map(str, cmd)
  
      log_output and LOG.info("Running command: %s", cmd)
      env = os.environ.copy()
      if addl_env:
          env.update(addl_env)
  
      obj = subprocess_popen(cmd, shell=False, stdin=subprocess.PIPE,
                             stdout=subprocess.PIPE, stderr=subprocess.PIPE,
                             env=env)
      return obj, cmd
docs: Create a process object for the given command.
  
      The return value will be a tuple of the process object and the
      list of command arguments used to create it.