text: var Book = Backbone.Model.extend({
    defaults: function(){
      return {
        title: "",
        author: "",
        thumbnail: "",
        genres: [],
        created_at: Date.now()
      }
    },
  
    validate: function(attributes) {
      var errors = {};
      if(_.isEmpty(attributes.title)){
        errors.title = "Must have a valid title";
      }
      if(_.isEmpty(attributes.author)){
        errors.author = "Must have a valid author";
      }
      return _.keys(errors).length ? errors : undefined;
    }
  });
  
  export default Book;
  