code: func ParseMethod(
  	fullMethod string) (version int32, service, methodName string, err error) {
  	rx := regexp.MustCompile(parseMethodPatt)
  	m := rx.FindStringSubmatch(fullMethod)
  	if len(m) == 0 {
  		return 0, "", "", fmt.Errorf("ParseMethod: invalid: %s", fullMethod)
  	}
  	v, err := strconv.ParseInt(m[1], 10, 32)
  	if err != nil {
  		return 0, "", "", fmt.Errorf("ParseMethod: %v", err)
  	}
  	return int32(v), m[2], m[3], nil
  }
docs: // ParseMethod parses a gRPC method and returns the CSI version, service
  // to which the method belongs, and the method's name. An example value
  // for the "fullMethod" argument is "/csi.v0.Identity/GetPluginInfo".