src/transformers/models/transfo_xl/tokenization_transfo_xl.py/TransfoXLCorpus/__init__
class TransfoXLCorpus:    def __init__(self, *args, **kwargs):
        self.vocab = TransfoXLTokenizer(*args, **kwargs)
        self.dataset = None
        self.train = None
        self.valid = None
        self.test = None