title: Django rest framework serializer data for empty queryset
body: <p>If there are no objects in a queryset, is there a way to send null values for all the attributes</p>
  <p>models.py</p>
  <pre><code>class ExampleModel(models.Model):
      key1 = models.CharField(max_length=100)
      key2 = models.CharField(max_length=100)
      key3 = models.CharField(max_length=100)
  </code></pre>
  <p>serializer.py</p>
  <pre><code>class ExampleModelSerializer(serializers.ModelSerializer):
      class Meta:
          model = ExampleModel
          fields = '__all__'
  </code></pre>
  <p>views.py</p>
  <pre><code>@api_view(['GET'])
  def objects_list(request):
      if ExampleModel.objects.all():
          objects = ExampleModel.objects.all()
          serializer = ExampleModelSerializer(objects, many=True)
          return Response(serializer.data)
      else:
          return Response('No Objects')
  </code></pre>
  <p>Here in this case if there are no objects then is there a way to get a response like this instead of a string</p>
  <pre><code>[    
      {
          &quot;id&quot;: null,
          &quot;key1&quot;: null,
          &quot;key2&quot;: null,
          &quot;key3&quot;: null,
      }
  ]
  </code></pre>