src/transformers/models/deberta_v2/tokenization_deberta_v2.py/SPMTokenizer/save_pretrained
class SPMTokenizer:    def save_pretrained(self, path: str, filename_prefix: str = None):
        filename = VOCAB_FILES_NAMES[list(VOCAB_FILES_NAMES.keys())[0]]
        if filename_prefix is not None:
            filename = filename_prefix + "-" + filename
        full_path = os.path.join(path, filename)
        with open(full_path, "wb") as fs:
            fs.write(self.spm.serialized_model_proto())
        return (full_path,)