assertStronglyEquivalent(network, ImmutableNetwork.copyOf(network));

    String networkString = network.toString();
    assertThat(networkString).contains("isDirected: " + network.isDirected());
    assertThat(networkString).contains("allowsParallelEdges: " + network.allowsParallelEdges());
    assertThat(networkString).contains("allowsSelfLoops: " + network.allowsSelfLoops());

   */
  public static <N> boolean hasCycle(Graph<N> graph) {
    int numEdges = graph.edges().size();
    if (numEdges == 0) {
      return false; // An edge-free graph is acyclic by definition.
    }
    if (!graph.isDirected() && numEdges >= graph.nodes().size()) {
      return true; // Optimization for the undirected case: at least one cycle must exist.
    }

    Map<Object, NodeVisitState> visitedNodes =

   */
  public static <N> boolean hasCycle(Graph<N> graph) {
    int numEdges = graph.edges().size();
    if (numEdges == 0) {
      return false; // An edge-free graph is acyclic by definition.
    }
    if (!graph.isDirected() && numEdges >= graph.nodes().size()) {
      return true; // Optimization for the undirected case: at least one cycle must exist.
    }

    Map<Object, NodeVisitState> visitedNodes =

  static <N> EndpointPair<N> of(Graph<?> graph, N nodeU, N nodeV) {
    return graph.isDirected() ? ordered(nodeU, nodeV) : unordered(nodeU, nodeV);
  }

  /** Returns an {@link EndpointPair} representing the endpoints of an edge in {@code network}. */
  static <N> EndpointPair<N> of(Network<?, ?> network, N nodeU, N nodeV) {
    return network.isDirected() ? ordered(nodeU, nodeV) : unordered(nodeU, nodeV);
  }

  /**

  static <N> EndpointPair<N> of(Graph<?> graph, N nodeU, N nodeV) {
    return graph.isDirected() ? ordered(nodeU, nodeV) : unordered(nodeU, nodeV);
  }

  /** Returns an {@link EndpointPair} representing the endpoints of an edge in {@code network}. */
  static <N> EndpointPair<N> of(Network<?, ?> network, N nodeU, N nodeV) {
    return network.isDirected() ? ordered(nodeU, nodeV) : unordered(nodeU, nodeV);
  }

  /**

   *
   * <ul>
   *   <li>A and B have equal {@link #isDirected() directedness}.
   *   <li>A and B have equal {@link #nodes() node sets}.
   *   <li>A and B have equal {@link #edges() edge sets}.
   *   <li>Every edge in A and B connects the same nodes in the same direction (if any).
   * </ul>
   *
   * <p>Network properties besides {@link #isDirected() directedness} do <b>not</b> affect equality.

/** `307 Temporary Redirect` (HTTP/1.1 - RFC 7231)  */
const val HTTP_TEMP_REDIRECT = 307

/** `308 Permanent Redirect` (HTTP/1.1 - RFC 7538)  */
const val HTTP_PERM_REDIRECT = 308

/** `421 Misdirected Request` (HTTP/2 - RFC 7540)  */

   *  * A client timeout (HTTP 408).
   *  * A authorization challenge (HTTP 401 and 407) that is satisfied by the [Authenticator].
   *  * A retryable server failure (HTTP 503 with a `Retry-After: 0` response header).
   *  * A misdirected request (HTTP 421) on a coalesced connection.
   */
  open fun isOneShot(): Boolean = false

  companion object {
    /** Empty request body with no content-type. */
    @JvmField

      MockResponse
        .Builder()
        .body("seed connection")
        .build(),
    )
    server.enqueue(
      MockResponse
        .Builder()
        .code(421)
        .body("misdirected!")
        .build(),
    )
    server.enqueue(
      MockResponse
        .Builder()
        .body("after misdirect")
        .build(),
    )

    // Seed the connection pool.