title: Foreign Key field always showing up as None in views.py, but not empty in database
body: <p>I have a django app that I want set up to have a worksheet object that has a list of section objects, where each section object has a list of answers.</p>
  
  <p>In the excerpt from my <strong>views.py</strong> shown below, I am trying to pass the first section associated with a worksheet to the render function. </p>
  
  <p>Whenever I get an individual section object in the following function within my <strong>views.py</strong> file, the section object does not have any answers associated with it. However, I know that the section I have gotten <em>does</em> have answers associated with it, because when I do a GET request (or look using the browsable API that is automatically setup by django rest framework), I can see that the section with the same id as the one I have in the function shown below in <strong>views.py</strong> has a long answers list as one of its attributes. </p>
  
  <p>Despite this, when I print out section.answers as shown below, myapp.Answer.None is displayed. </p>
  
  <p><strong>views.py</strong></p>
  
  <pre><code>def worksheet_detail(request, pk):
      worksheet = Worksheet.objects.get(pk=pk)
      sections = Section.objects.filter(worksheet=worksheet)
      sections = list(sections)
      section = sections[1]
      print(section.answers)
      print(section.id)
      return render(request, 'worksheets/worksheet_detail.html', {
          'worksheet': worksheet,
          'section': section,
      })
  </code></pre>
  
  <p><strong>models.py</strong></p>
  
  <pre><code>class Worksheet(models.Model):
      created = models.DateTimeField(auto_now_add=True)
      name = models.CharField(max_length=100, unique=True, default='')
  
  
  class Section(models.Model):
      created = models.DateTimeField(auto_now_add=True)
      name = models.CharField(max_length=100, unique=True, default='')
      worksheet = models.ForeignKey(
          Worksheet, related_name='sections', null=True)
  
      class Meta:
          ordering = ('created',)
  
  
  class Answer(models.Model):
      created = models.DateTimeField(auto_now_add=True)
      student_name = models.CharField(max_length=100, blank=True, 
                                      default='')
      num = models.IntegerField(default=0)
      section = models.ForeignKey(Section, related_name='answers', 
                                  null=True)
  </code></pre>
  
  <p><strong>serializers.py</strong>   </p>
  
  <pre><code>class AnswerSerializer(serializers.HyperlinkedModelSerializer):
  
      class Meta:
          model = Answer
          fields = ('student_name', 'section', 'num', 'id',)
  
  class SectionSerializer(serializers.HyperlinkedModelSerializer):
      answers = AnswerSerializer(many=True)
  
      def create(self, validated_data):
          answers_data = validated_data.pop('answers')
          section = Section.objects.create(**validated_data)
          for answer_data in answers_data:
              Answer.objects.create(section=section, **answer_data)
          return section
  
      class Meta:
          model = Section
          fields = ('name', 'worksheet', 'answers', 'id',)
  
  class WorksheetSerializer(serializers.HyperlinkedModelSerializer):
      sections = SectionSerializer(many=True)
  
      def create(self, validated_data):
          sections_data = validated_data.pop('sections')
          worksheet = Worksheet.objects.create(**validated_data)
          for section_data in sections_data:
              Section.objects.create(worksheet=worksheet, **section_data)
          return section
  
      class Meta:
          model = Worksheet
          fields = ('name','id', 'sections')
  </code></pre>