protocol JSONRepresentation{
    func to_json() -> String
}

extension JSONRepresentation{
    func to_json() -> String
    {
        let reflection = Mirror(reflecting: self)
        let root = String(describing: reflection.subjectType).lowercased()
        var children :[String:Any]  = [:]
        reflection.children.forEach { (child) in
            children[child.label!] = child.value
        }
        let hash = [
            root:children
        ]
        let jsonData = try! JSONSerialization.data(withJSONObject: hash, options: .prettyPrinted)
        let json = String(bytes: jsonData, encoding: .utf8)!
        return json

    }

}