src/transformers/models/whisper/tokenization_whisper.py/WhisperTokenizer/_convert_id_to_token
class WhisperTokenizer:    def _convert_id_to_token(self, index):
        """
        Converts an index (integer) in a token (str) using the vocab. Whisper's base tokenizer always decodes OOV
        tokens as "", thus we do not use the `unk_token` here.
        """
        return self.decoder.get(index, "")