network = createGraph();
    if (network instanceof MutableNetwork) {
      networkAsMutableNetwork = (MutableNetwork<Integer, String>) network;
    }
  }

  @After
  public void validateNetworkState() {
    validateNetwork(network);
  }

  static <N, E> void validateNetwork(Network<N, E> network) {
    assertStronglyEquivalent(network, Graphs.copyOf(network));