code: func printError(err error) {
  	// Do nothing is the error is errCmdArgsParse.
  	if err == errCmdArgsParse {
  		return
  	}
  
  	fmt.Fprintln(os.Stderr, err)
  
  	// Print the help of the GMQ Client commands if the error is errInvalidCmdName.
  	if err == errInvalidCmdName {
  		fmt.Println()
  		printHelp()
  	}
  }
docs: // printError prints the error to the standard error.