      <field name="author" rel="ManyToOneRel" to="serializers.author">%(author_pk)s</field>
      <field name="headline" type="CharField">Poker has no place on ESPN</field>
      <field name="pub_date" type="DateTimeField">2006-06-16T11:00:00</field>
      <field name="categories" rel="ManyToManyRel" to="serializers.category"><object pk="%(first_category_pk)s"></object><object pk="%(second_category_pk)s"></object></field>
    </object>
  </django-objects>"""
  
      @staticmethod
      def _comparison_value(value):
          # The XML serializer handles everything as strings, so comparisons
 
</s> remove     pass
 </s> add     @classmethod
    def WithData(cls, original_exc, model, fk, field_value):
        """
        Factory method for creating a deserialization error which has a more
        explanatory messsage.
        """
        return cls("%s: (%s:pk=%s) field_value was '%s'" % (original_exc, model, fk, field_value)) </s> remove                             value = field.remote_field.model._meta.get_field(field.remote_field.field_name).to_python(field_value)
                        data[field.attname] = value
                    else:
                        data[field.attname] = field.remote_field.model._meta.get_field(field.remote_field.field_name).to_python(field_value)
 </s> add                             data[field.attname] = field.remote_field.model._meta.get_field(field.remote_field.field_name).to_python(field_value)
                    except Exception as e:
                        raise base.DeserializationError.WithData(e, d['model'], d.get('pk'), field_value)
    <field name="meta_data" rel="ManyToManyRel" to="serializers.categorymetadata"></field>
      <field name="author" rel="ManyToOneRel" to="serializers.author">%(author_pk)s</field>
      <field name="headline" type="CharField">Poker has no place on ESPN</field>
      <field name="pub_date" type="DateTimeField">2006-06-16T11:00:00</field>
      <field name="categories" rel="ManyToManyRel" to="serializers.category"><object pk="%(first_category_pk)s"></object><object pk="%(second_category_pk)s"></object></field>
    <field name="meta_data" rel="ManyToManyRel" to="serializers.categorymetadata"></field>
    </object>
  </django-objects>"""
  
      @staticmethod
      def _comparison_value(value):
          # The XML serializer handles everything as strings, so comparisons
keep keep keep add keep keep keep keep keep keep
 Fixed #19820 -- Added more helpful error messages to Python deserializer. 
tests/serializers/tests.py