src/transformers/models/marian/convert_marian_tatoeba_to_pytorch.py/TatoebaConverter/resolve_lang_code
class TatoebaConverter:    def resolve_lang_code(self, src, tgt) -> Tuple[str, str]:
        src_tags = self.get_tags(src, self.tag2name[src])
        tgt_tags = self.get_tags(tgt, self.tag2name[tgt])
        return src_tags, tgt_tags