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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def splits(cls, text_field, root='.data', train='wiki.train.tokens', validation='wiki.valid.tokens', test='wiki.test.tokens', **kwargs):
 """Create dataset objects for splits of the WikiText-2 dataset. This is the most flexible way to use the dataset. Arguments: text_field: The field that will be used for text data. root: The root directory that the dataset's zip archive will be expanded into; therefore the directory in whose wikitext-2 subdirectory the data files will be stored. train: The filename of the train data. Default: 'wiki.train.tokens'. validation: The filename of the validation data, or None to not load the validation set. Default: 'wiki.valid.tokens'. test: The filename of the test data, or None to not load the test set. Default: 'wiki.test.tokens'. """

        return super(WikiText2, cls).splits(
            root=root, train=train, validation=validation, test=test,
            text_field=text_field, **kwargs)