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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 untranscribed_batch_gen(self):
 """ A batch generator for all the untranscribed data. """


        feat_fns = self.corpus.get_untranscribed_fns()
        fn_batches = self.make_batches(feat_fns)

        for fn_batch in fn_batches:
            batch_inputs, batch_inputs_lens = utils.load_batch_x(fn_batch,
                                                             flatten=False)
            yield batch_inputs, batch_inputs_lens, fn_batch