def _convert_id_to_token(self, index: int) -> str:
        """Converts an index (integer) in a token (str) using the decoder."""
        if index in self.id_to_lang_token:
            return self.id_to_lang_token[index]
        return self.decoder.get(index, self.unk_token)
Converts an index (integer) in a token (str) using the decoder.
dpkd/transformers/src/transformers/models/m2m_100/tokenization_m2m_100.py