def METHOD_NAME(self):
    reg_maxtrix = self.reg.deriv2(self.true_model)
    dmis_matrix = self.G.T.dot((self.dmis.W**2).dot(self.G))
    combo_matrix = dmis_matrix + self.beta * reg_maxtrix
    max_eigenvalue_numpy, _ = eigsh(combo_matrix, k=1)
    max_eigenvalue_directive = eigenvalue_by_power_iteration(
        self.mixcombo, self.true_model, n_pw_iter=100
    )
    passed = np.isclose(max_eigenvalue_numpy, max_eigenvalue_directive, rtol=1e-2)
    self.assertTrue(passed, True)
    print("Eigenvalue Utils for a mixed ComboObjectiveFunction is validated.")