public HumanType(StarWarsData data)
        {
            Name = "Human";

            Field(h => h.Id).Description("The id of the human.");
            Field(h => h.Name, true).Description("The name of the human.");

            Field <ListGraphType <CharacterInterface> >(
                "friends",
                resolve: context => data.GetFriends(context.Source)
                );

            Interface <CharacterInterface>();
        }