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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 proximal(self):
 """Proximal factory of the quadratically perturbed functional."""

        if self.quadratic_coeff < 0:
            raise TypeError('`quadratic_coeff` {} must be non-negative'
                            ''.format(self.quadratic_coeff))

        return proximal_quadratic_perturbation(
            self.functional.proximal,
            a=self.quadratic_coeff, u=self.linear_term)