  
      def test_update(self):
          serializer = CommentSerializer(self.comment, data=self.data)
          self.assertEquals(serializer.is_valid(), False)
          self.assertEquals(serializer.errors, {'content': [u'Ensure this value has at most 1000 characters (it has 1001).']})
  
      def test_update_missing_field(self):
          data = {
              'content': 'xxx',
              'created': datetime.datetime(2012, 1, 1)
 
</s> remove         self.assertEquals(serializer.errors, {'content': [u'Ensure this value has at most 1000 characters (it has 1001).']})
 </s> add         self.assertEquals(serializer.errors, {'content': ['Ensure this value has at most 1000 characters (it has 1001).']}) </s> remove         self.assertEquals(serializer.errors, {'title': [u'Ensure this value has at most 200 characters (it has 201).']})
 </s> add         self.assertEquals(serializer.errors, {'title': ['Ensure this value has at most 200 characters (it has 201).']}) </s> remove         self.assertEquals(serializer.errors, {'info': [u'Ensure this value has at most 12 characters (it has 13).']})
 </s> add         self.assertEquals(serializer.errors, {'info': ['Ensure this value has at most 12 characters (it has 13).']}) </s> remove         self.assertEquals(serializer.errors, {'email': [u'This field is required.']})
 </s> add         self.assertEquals(serializer.errors, {'email': ['This field is required.']}) </s> remove         self.assertEquals(serializer.errors, {'isbn': [u'isbn has to be exact 13 numbers']})
 </s> add         self.assertEquals(serializer.errors, {'isbn': ['isbn has to be exact 13 numbers']})
        self.assertEquals(serializer.errors, {'content': ['Ensure this value has at most 1000 characters (it has 1001).']})
  
      def test_update(self):
          serializer = CommentSerializer(self.comment, data=self.data)
          self.assertEquals(serializer.is_valid(), False)
        self.assertEquals(serializer.errors, {'content': ['Ensure this value has at most 1000 characters (it has 1001).']})
  
      def test_update_missing_field(self):
          data = {
              'content': 'xxx',
              'created': datetime.datetime(2012, 1, 1)
keep keep keep keep replace keep keep keep keep keep
 First passing test under p3k \o/ 
rest_framework/tests/serializer.py