class Ground { final String answer; final List shouldContain; final List shouldNotContain; final List files; final Map eval; Ground({ required this.answer, required this.shouldContain, required this.shouldNotContain, required this.files, required this.eval, }); factory Ground.fromJson(Map json) { return Ground( answer: json['answer'] ?? "", shouldContain: List.from(json['should_contain'] ?? []), shouldNotContain: List.from(json['should_not_contain'] ?? []), files: List.from(json['files'] ?? []), eval: json['eval'] ?? {}, ); } }