def METHOD_NAME(self, dimensions, n_excitations):
    iden = qutip.enr_identity(dimensions, n_excitations)
    expected_size = _n_enr_states(dimensions, n_excitations)
    expected_shape = (expected_size, expected_size)
    assert np.all(iden.diag() == 1)
    assert np.all(iden.full() - np.diag(iden.diag()) == 0)
    assert iden.shape == expected_shape
    assert iden.dims == [dimensions, dimensions]