def METHOD_NAME(self):
    net = op.network.Cubic(shape=[5, 5, 5])
    P12 = net['throat.conns'][0]
    extend(network=net, throat_conns=[P12])
    a = op.utils.check_network_health(net)
    assert len(a['duplicate_throats']) == 1
    assert a['duplicate_throats'][0] == 300