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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 iters(cls, batch_size=32, bptt_len=35, device=0, root='.data', vectors=None, **kwargs):
 """Create iterator objects for splits of the WikiText-2 dataset. This is the simplest way to use the dataset, and assumes common defaults for field, vocabulary, and iterator parameters. Arguments: batch_size: Batch size. bptt_len: Length of sequences for backpropagation through time. device: Device to create batches on. Use -1 for CPU and None for the currently active GPU device. 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. wv_dir, wv_type, wv_dim: Passed to the Vocab constructor for the text field. The word vectors are accessible as train.dataset.fields['text'].vocab.vectors. Remaining keyword arguments: Passed to the splits method. """

        TEXT = data.Field()

        train, val, test = cls.splits(TEXT, root=root, **kwargs)

        TEXT.build_vocab(train, vectors=vectors)

        return data.BPTTIterator.splits(
            (train, val, test), batch_size=batch_size, bptt_len=bptt_len,
            device=device)