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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_one_iter(self):
 """Rollback one iteration. Returns ------- self : Booster Booster with rolled back one iteration. """

        _safe_call(_LIB.LGBM_BoosterRollbackOneIter(
            self.handle))
        self.__is_predicted_cur_iter = [False for _ in range_(self.__num_dataset)]
        return self