title: Django rest framework - cant serialize query set
body: <p>I try to serialize query set</p>
  
  <pre><code>def do(self):
          reservations = Reservation.objects.all()
          serializer = ReservationSerializer(data=reservations, many=True)
          if serializer.is_valid():
              encoded_data = json.dumps(serializer.data)
              r = requests.post('http://httpbin.org/post', headers={'Content-Type': 'application/json'}, data=encoded_data)
              print(r.text)
          else:
              print(serializer.errors)
  </code></pre>
  
  <p>And I always get error of </p>
  
  <blockquote>
    <p>{u'non_field_errors': [u'Expected a list of items but got type "QuerySet".']}</p>
  </blockquote>
  
  <p>I tried to use <code>values()</code> on query set, and then convert to list, but this way I get objects without nested models</p>
  
  <p><strong>model</strong></p>
  
  <pre><code>class Reservation(models.Model):
      start = models.DateField(verbose_name='Заезд', auto_now=False, auto_now_add=False, blank=False)
      end = models.DateField(verbose_name='Выезд', auto_now=False, auto_now_add=False, blank=False)
      check_in_time = models.TimeField(verbose_name='Время заезда', blank=False)
      check_out_time = models.TimeField(verbose_name='Время выезда', blank=False)
      has_refund = models.BooleanField(verbose_name='Возвратная бронь', default=True)
      payed = models.BooleanField(verbose_name='Оплачено', default=False)
      reserved_days = models.ManyToManyField(Day, blank=False)
      additional_services = models.ManyToManyField(AdditionalService)
      guest_name = models.CharField(verbose_name='Имя гостя', max_length=200, blank=True)
      reservation_number = models.CharField(verbose_name='Номер брони', max_length=200, blank=True)
  
  class AdditionalService(models.Model):
      payment_date = models.CharField(verbose_name='Дата оплаты', max_length=200, blank=True)
      payment_type = models.CharField(verbose_name='Форма оплаты', max_length=200, blank=False)
      service = models.CharField(verbose_name='Услуга', max_length=200, blank=False)
      quantity = models.IntegerField(blank=False)
      price = models.FloatField(blank=False)
  
  class Day(models.Model):
      date = models.DateField(auto_now=False, auto_now_add=False)
      price = models.FloatField()
      payment_method = models.CharField(max_length = 200, blank=True)
      payment_date = models.CharField(max_length=200, blank=True)
      room = models.ForeignKey(Room, null=True, blank=True, verbose_name='Номер', on_delete=models.CASCADE)
  
  class Room(models.Model):
      name = models.CharField(max_length = 200, null=True)
      id = models.AutoField(primary_key=True)
      room_id = models.CharField(max_length = 200, null=False)
  
      def __unicode__(self):
          return self.name
  </code></pre>
  
  <p><strong>serializers</strong></p>
  
  <pre><code>class ReservationSerializer(serializers.ModelSerializer):
      reserved_days = DaySerializer(many=True)
      additional_services = AdditionalServicesSerializer(many=True)
  
      class Meta:
          model = Reservation
          fields = [
              'start',
              'end',
              'check_in_time',
              'check_out_time',
              'reserved_days',
              'additional_services',
              'has_refund',
              'payed',
              'guest_name',
              'reservation_number',
          ]
  
  class DaySerializer(serializers.ModelSerializer):
      room = RoomSerializer()
  
      class Meta:
          model = Day
          fields = [
              'date',
              'price',
              'payment_method',
              'payment_date',
              'room',
          ]
  
  class AdditionalServicesSerializer(serializers.ModelSerializer):
      class Meta:
          model = AdditionalService
          fields = [
              'payment_date',
              'payment_type',
              'service',
              'quantity',
              'price',
          ]
  
  class RoomSerializer(serializers.ModelSerializer):
      class Meta:
          model = Room
          fields = [
              'room_id',
          ]
  </code></pre>