/**
   * Returns a view of {@code network} with the direction (if any) of every edge reversed. All other
   * properties remain intact, and further updates to {@code network} will be reflected in the view.
   */
  public static <N, E> Network<N, E> transpose(Network<N, E> network) {
    if (!network.isDirected()) {
      return network; // the transpose of an undirected network is an identical network
    }

 *
 * Two instances must be used to get all results for an address.
 *
 * @param network network to use, if not selects the default network.
 */
@RequiresApi(Build.VERSION_CODES.Q)
@ExperimentalOkHttpApi
class AndroidAsyncDns(
  private val dnsClass: AsyncDns.DnsClass,
  private val network: Network? = null,
) : AsyncDns {
  @RequiresApi(Build.VERSION_CODES.Q)
  internal val resolver = DnsResolver.getInstance()

    setDistinctValues(MutableNetwork.class, mutableNetworkA, mutableNetworkB);
    setDistinctValues(NetworkBuilder.class, NETWORK_BUILDER_A, NETWORK_BUILDER_B);
    setDistinctValues(Network.class, IMMUTABLE_NETWORK_A, IMMUTABLE_NETWORK_B);
    setDefault(EndpointPair.class, EndpointPair.ordered("A", "B"));
  }

  @Override
  public void testNulls() throws Exception {
    try {

    for (MutableNetwork<Integer, String> network : networksToTest) {
      network.addEdge(1, 2, "1-2a");
      network.addEdge(1, 2, "1-2b");
    }
    assertThat(hasCycle(directedNetwork)).isFalse();
    assertThat(hasCycle(undirectedNetwork)).isTrue(); // cyclic in undirected case
  }

  @Test
  public void hasCycle_cyclicMultigraph() {
    for (MutableNetwork<Integer, String> network : networksToTest) {

    /**
     * Indicates whether network access to remote repositories has been disabled.
     *
     * @return {@code true} if remote access has been disabled, {@code false} otherwise.
     */
    boolean isOffline();

    /**
     * Enables/disables network access to remote repositories.
     *
     * @param offline {@code true} to disable remote access, {@code false} to allow network access.

    return Maps.asMap(network.edges(), network::incidentNodes);
  }

  var responder: (Request) -> Unit = {
    it.callback.onAnswer(listOf(), 0)
  }

  data class Request(
    val network: Network?,
    val domain: String,
    val nsType: Int,
    val flags: Int,
    val callback: DnsResolver.Callback<List<InetAddress>>,
  )

  @Implementation
  fun query(
    network: Network?,
    domain: String,
    nsType: Int,
    flags: Int,
    executor: Executor,

    for (MutableNetwork<Integer, String> network : networksToTest) {
      network.addEdge(1, 2, "1-2a");
      network.addEdge(1, 2, "1-2b");
    }
    assertThat(hasCycle(directedNetwork)).isFalse();
    assertThat(hasCycle(undirectedNetwork)).isTrue(); // cyclic in undirected case
  }

  @Test
  public void hasCycle_cyclicMultigraph() {
    for (MutableNetwork<Integer, String> network : networksToTest) {

  }

  static void assertStronglyEquivalent(Network<?, ?> networkA, Network<?, ?> networkB) {
    // Properties not covered by equals()
    assertThat(networkA.allowsParallelEdges()).isEqualTo(networkB.allowsParallelEdges());
    assertThat(networkA.allowsSelfLoops()).isEqualTo(networkB.allowsSelfLoops());
    assertThat(networkA.nodeOrder()).isEqualTo(networkB.nodeOrder());
    assertThat(networkA.edgeOrder()).isEqualTo(networkB.edgeOrder());

  }

  static void assertStronglyEquivalent(Network<?, ?> networkA, Network<?, ?> networkB) {
    // Properties not covered by equals()
    assertThat(networkA.allowsParallelEdges()).isEqualTo(networkB.allowsParallelEdges());
    assertThat(networkA.allowsSelfLoops()).isEqualTo(networkB.allowsSelfLoops());
    assertThat(networkA.nodeOrder()).isEqualTo(networkB.nodeOrder());
    assertThat(networkA.edgeOrder()).isEqualTo(networkB.edgeOrder());