title: How add nested attributes in the seeds file Rails
body: <p>I have model Exhibit and he have quiz. In quiz we have questions and answers belongs to it. I used nested attributes.</p>
  
  <p>Where I make mistake, because wright now after rake db:seed rails add me only last line in Question. Here is example one of my seeds exhibit</p>
  
  <pre><code>e1 = Exhibit.create(
  title: 'TITLE', 
  author:  'PICASOO',
  date_of_origin: '300', 
  description: 'LOREM IPSUM', 
  ex_id: '1',
  type: nil,
      questions_attributes:[
      content: "QUESTION 1?",
          answers_attributes:[
          content: "ANSWER 1",
          correct: true,
          content: "ANSWER 2",
          correct: false, # if it's correct answer i change this var.
          content: "ANSWER 3",
          correct: false]
      ])
  </code></pre>
  
  <p>Exhibit model:</p>
  
  <pre><code>has_many :questions, :dependent=&gt; :destroy
    accepts_nested_attributes_for :questions, 
                                  :reject_if =&gt; lambda { |a| a[:content].blank? }, 
                                  :allow_destroy =&gt; true
  </code></pre>
  
  <p>Question model:</p>
  
  <pre><code> belongs_to :exhibit
        has_many :answers, :dependent=&gt; :destroy
        accepts_nested_attributes_for :answers,
                                      :reject_if =&gt; lambda { |a| a[:content].blank? }, 
                                      :allow_destroy =&gt; true
  </code></pre>
  
  <p>Answer model:</p>
  
  <pre><code>class Answer &lt; ActiveRecord::Base
    belongs_to :question
  end
  </code></pre>