open class RealmModel: Object {
    // MARK: - Properties
    
    @objc dynamic var id: Int = nextID()
    
    // MARK: - Internal
    
    private static func nextID() -> Int {
        return RealmService.shared.nextID(for: self)
    }
    
    // MARK: - Realm
    
    open override class func primaryKey() -> String? {
        return "id"
    }
}