code: def convex_conj(self):
          
          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)
docs: The convex conjugate