def load_dataset(self, split, epoch=0, combine=False, **kwargs):
        """Load a given dataset split.

        Args:
            split (str): name of the split (e.g., train, valid, test)
        """
        paths = self.args.data.split(':')
        assert len(paths) > 0
        data_path = paths[epoch % len(paths)]

        # infer langcode
        src, tgt = self.args.source_lang, self.args.target_lang

        self.datasets[split] = load_langpair_dataset(
            data_path, split, src, self.src_dict, tgt, self.tgt_dict,
            combine=combine, dataset_impl=self.args.dataset_impl,
            upsample_primary=self.args.upsample_primary,
            left_pad_source=self.args.left_pad_source,
            left_pad_target=self.args.left_pad_target,
            max_source_positions=self.args.max_source_positions,
            max_target_positions=self.args.max_target_positions,
            load_alignments=self.args.load_alignments,
            truncate_source=self.args.truncate_source,
        )
Load a given dataset split.

        Args:
            split (str): name of the split (e.g., train, valid, test)
        
infoxlm/fairseq/fairseq/tasks/translation.py