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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 next(self):
 """For python 2.x. # Returns The next batch. """

        # Keeps under lock only the mechanism which advances
        # the indexing of each batch.
        with self.lock:
            index_array = next(self.index_generator)
        # The transformation of images is not under thread lock
        # so it can be done in parallel
        return self._get_batches_of_transformed_samples(index_array)