assertThat(graph.isDirected()).isEqualTo(asNetwork.isDirected());
    assertThat(graph.allowsSelfLoops()).isEqualTo(asNetwork.allowsSelfLoops());
    assertThat(asNetwork.edgeOrder()).isEqualTo(ElementOrder.unordered());
    assertThat(asNetwork.allowsParallelEdges()).isFalse();
    assertThat(asNetwork.asGraph()).isEqualTo(graph);

    Set<EndpointPair<N>> allEndpointPairs = new HashSet<>();

    assertThat(graph.isDirected()).isEqualTo(asNetwork.isDirected());
    assertThat(graph.allowsSelfLoops()).isEqualTo(asNetwork.allowsSelfLoops());
    assertThat(asNetwork.edgeOrder()).isEqualTo(ElementOrder.unordered());
    assertThat(asNetwork.allowsParallelEdges()).isFalse();
    assertThat(asNetwork.asGraph()).isEqualTo(graph);

    Set<EndpointPair<N>> allEndpointPairs = new HashSet<>();

   * network that does not allow them will throw an {@link IllegalArgumentException}.
   */
  boolean allowsParallelEdges();

  /** Returns the order of iteration for the elements of {@link #edges()}. */
  ElementOrder<E> edgeOrder();

  //
  // Element-level accessors
  //

  /**
   * Returns a live view of the edges whose {@link #incidentNodes(Object) incident nodes} in this
   * network include {@code node}.