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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 _solve(self, sense=None):
 """Remove old constraints and then solve the current problem. Args: sense: Minimize or maximize the objective. (:class:`.lp.ObjectiveSense) Returns: The Result object for the solved LP problem """

        # Remove the constraints from the last run
        while len(self._remove_constr) > 0:
            self._remove_constr.pop().delete()

        try:
            return self._prob.solve(sense=sense)
        except lp.SolverError as e:
            raise_from(MOMAError(text_type(e)), e)
        finally:
            self._remove_constr = []