def additional_special_tokens(self) -> List[str]:
        """
        `List[str]`: All the additional special tokens you may want to use. Log an error if used while not having been
        set.
        """
        if self._additional_special_tokens is None:
            if self.verbose:
                logger.error("Using additional_special_tokens, but it is not set yet.")
            return None
        return [str(tok) for tok in self._additional_special_tokens]

        `List[str]`: All the additional special tokens you may want to use. Log an error if used while not having been
        set.
        
dpkd/transformers/src/transformers/tokenization_utils_base.py