class Airport { final String? id; final String? city; final String? code; final String? name; Airport({this.id, required this.city, required this.code, required this.name}); factory Airport.fromMap(Map map, String documentId) { return Airport( id: documentId, city: map['city'] as String?, code: map['kode'] as String?, name: map['name'] as String?, ); } }