code: func (fv FlagValues) Int(name string, defaultValue int) (int, error) {
  	value, found := fv[name]
  	if !found {
  		return defaultValue, nil
  	}
  	i, err := strconv.Atoi(value)
  	if err != nil {
  		return 0, fmt.Errorf("flag %q: cannot parse integer from %q", name, value)
  	}
  	return i, nil
  }
docs: // Int returns the integer version of a flag, if set.