code: func extractIptablesVersion(str string) (int, int, int, error) {
  	versionMatcher := regexp.MustCompile("v([0-9]+)\\.([0-9]+)\\.([0-9]+)")
  	result := versionMatcher.FindStringSubmatch(str)
  	if result == nil {
  		return 0, 0, 0, fmt.Errorf("no iptables version found in string: %s", str)
  	}
  
  	v1, err := strconv.Atoi(result[1])
  	if err != nil {
  		return 0, 0, 0, err
  	}
  
  	v2, err := strconv.Atoi(result[2])
  	if err != nil {
  		return 0, 0, 0, err
  	}
  
  	v3, err := strconv.Atoi(result[3])
  	if err != nil {
  		return 0, 0, 0, err
  	}
  
  	return v1, v2, v3, nil
  }
docs: // getIptablesVersion returns the first three components of the iptables version.
  // e.g. "iptables v1.3.66" would return (1, 3, 66, nil)