  
      def test_url_field(self):
          self.field_test('url_field')
  
  
  class DefaultValuesOnAutogeneratedFieldsTests(TestCase):
  
      def setUp(self):
          class DVOAFModel(RESTFrameworkModel):
              positive_integer_field = models.PositiveIntegerField(blank=True)
 
</s>
    def test_nullable_char_field(self):
        self.field_test('nullable_char_field')

  
      def test_url_field(self):
          self.field_test('url_field')
  
    def test_nullable_char_field(self):
        self.field_test('nullable_char_field')

  
  class DefaultValuesOnAutogeneratedFieldsTests(TestCase):
  
      def setUp(self):
          class DVOAFModel(RESTFrameworkModel):
              positive_integer_field = models.PositiveIntegerField(blank=True)
keep keep keep add keep keep keep keep keep keep
 Test for setting allow_none=True for nullable CharFields
rest_framework/tests/test_serializer.py