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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 convex_conj(self):
 """Convex conjugate functional of IndicatorLpUnitBall. Returns ------- convex_conj : GroupL1Norm The convex conjugate is the the group L1-norm. """

        conj_exp = conj_exponent(self.pointwise_norm.exponent)
        return GroupL1Norm(self.domain, exponent=conj_exp)