code: def raw_dataset(self):
          
          dataset = {}
          queryset = self.queryset.values_list(*(['pk'] + self.fields))
          if self.limit:
              queryset = queryset[:self.limit]
          for item in queryset:
              item = list(item)
              item_pk = item.pop(0)
              datas = ' '.join(map(six.text_type, item))
              dataset[item_pk] = self.raw_clean(datas)
          return dataset
docs: Generate a raw dataset based on the queryset
          and the specified fields.