code: func label(l string, indent, width int) string {
  	pad := width - indent - len(l)
  	if pad < 0 {
  		pad = 0
  	}
  	return fmt.Sprintf("%s%s%s", strings.Repeat(" ", indent), l,
  		strings.Repeat(" ", pad))
  }
docs: // label returns a string containing the label with indentation and padding.