def METHOD_NAME():
    net, expected_bb, expected_bbr = boundary_testnet("case9_27")
    geq.set_bus_zone_by_boundary_branches(net, expected_bbr)
    assert all(net.bus.zone.values == np.array([0, 1, 1, 0, 0, 1, 1, 1, 0]))
    boundary_buses, boundary_branches = \
        geq.get_boundaries_by_bus_zone_with_boundary_branches(net)
    assert boundary_buses == expected_bb
    assert boundary_branches["all"] == expected_bbr
    # --- test against set_bus_zone_by_boundary_branches()
    bb_in = {"line": {2, 4, 7}}
    geq.set_bus_zone_by_boundary_branches(net, bb_in)
    assert all(net.bus.zone.values == np.array([0, 1, 2, 0, 0, 2, 1, 1, 0]))