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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):
 """The convex conjugate"""

        if isinstance(self.domain, ProductSpace):
            norm = GroupL1Norm(self.domain, 2)
        else:
            norm = L1Norm(self.domain)

        return FunctionalQuadraticPerturb(norm.convex_conj,
                                          quadratic_coeff=self.gamma / 2)