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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 rollback(self):
 """Rolls back the current batch. Marks the batch as aborted (can't be used again). Overridden by :class:`google.cloud.datastore.transaction.Transaction`. :raises: :class:`~exceptions.ValueError` if the batch is not in progress. """

        if self._status != self._IN_PROGRESS:
            raise ValueError("Batch must be in progress to rollback()")

        self._status = self._ABORTED