def train(
        self,
        files: Union[str, List[str]],
        vocab_size: int = 30000,
        min_frequency: int = 2,
        special_tokens: List[str] = ["<unk>"],
        limit_alphabet: int = 1000,
        initial_alphabet: List[str] = [],
        suffix: Optional[str] = "</w>",
        show_progress: bool = True,
    ):
        """ Train the model using the given files """

        trainer = BpeTrainer(
            vocab_size=vocab_size,
            min_frequency=min_frequency,
            special_tokens=special_tokens,
            limit_alphabet=limit_alphabet,
            initial_alphabet=initial_alphabet,
            end_of_word_suffix=suffix,
            show_progress=show_progress,
        )
        if isinstance(files, str):
            files = [files]
        self._tokenizer.train(trainer, files)
 Train the model using the given files 
xtune/src/transformers/tokenization_openai.py