code: def subsets(self):
      
      source, target = self.builder_config.language_pair
      filtered_subsets = {}
      for split, ss_names in self._subsets.items():
        filtered_subsets[split] = []
        for ss_name in ss_names:
          ds = DATASET_MAP[ss_name]
          if ds.target != target or source not in ds.sources:
            logging.info(
                "Skipping sub-dataset that does not include language pair: %s",
                ss_name)
          else:
            filtered_subsets[split].append(ss_name)
      logging.info("Using sub-datasets: %s", filtered_subsets)
      return filtered_subsets
docs: Subsets that make up each split of the dataset for the language pair.