code: func OutputFormat(s string) string {
  	var buf bytes.Buffer
  	for _, old := range s {
  		if newVal, ok := replace[old]; ok {
  			buf.WriteString(newVal)
  			continue
  		}
  		buf.WriteRune(old)
  	}
  
  	return buf.String()
  }
docs: // OutputFormat output escape character with backslash.