func (r Ref) ID() string {
	if refIF, ok := r["$ref"]; ok {
		return strings.TrimPrefix(refIF.(string), "#/definitions/")
	}
	return ""
}
func (r Ref) ID() string {
	if refIF, ok := r["$ref"]; ok {
		return strings.TrimPrefix(refIF.(string), "#/definitions/")
	}
	return ""
}
// ID of the reference