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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 objective_bounds(self):
 """ Return objective bounds Returns ------- lower : list of floats Lower boundaries for the objectives Upper : list of floats Upper boundaries for the objectives """

        if self.ideal and self.nadir:
            return self.ideal, self.nadir
        raise NotImplementedError(
            "Ideal and nadir value calculation is not yet implemented"
        )