src/transformers/models/reformer/tokenization_reformer_fast.py/ReformerTokenizerFast/__init__
class ReformerTokenizerFast:    def __init__(
        self,
        vocab_file=None,
        tokenizer_file=None,
        eos_token="</s>",
        unk_token="<unk>",
        additional_special_tokens=[],
        **kwargs
    ):
        super().__init__(
            vocab_file,
            tokenizer_file=tokenizer_file,
            eos_token=eos_token,
            unk_token=unk_token,
            additional_special_tokens=additional_special_tokens,
            **kwargs,
        )

        self.vocab_file = vocab_file
        self.can_save_slow_tokenizer = False if not self.vocab_file else True