input.put("foo", 3);
    input.put("foo", 1);
    ImmutableSetMultimap<Object, Object> copy = ImmutableSetMultimap.copyOf(input);
    assertEquals(3, copy.size());
  }

  public void testCopyOfEmpty() {
    HashMultimap<String, Integer> input = HashMultimap.create();
    Multimap<String, Integer> multimap = ImmutableSetMultimap.copyOf(input);
    assertEquals(multimap, input);
    assertEquals(input, multimap);
  }

  }

  @Test
  public void copyOfImmutableNetwork_optimized() {
    Network<String, String> network1 =
        ImmutableNetwork.copyOf(NetworkBuilder.directed().<String, String>build());
    Network<String, String> network2 = ImmutableNetwork.copyOf(network1);

    assertThat(network2).isSameInstanceAs(network1);
  }

  @Test
  public void edgesConnecting_directed() {

    return copyOf(elements);
  }

  public static <E> ImmutableList<E> copyOf(Iterable<? extends E> elements) {
    checkNotNull(elements); // for GWT
    return (elements instanceof Collection)
        ? copyOf((Collection<? extends E>) elements)
        : copyOf(elements.iterator());
  }

  public static <E> ImmutableList<E> copyOf(Iterator<? extends E> elements) {

  protected abstract <E extends Comparable<? super E>> Set<E> copyOf(E[] elements);

  protected abstract <E extends Comparable<? super E>> Set<E> copyOf(
      Collection<? extends E> elements);

  protected abstract <E extends Comparable<? super E>> Set<E> copyOf(
      Iterable<? extends E> elements);

  protected abstract <E extends Comparable<? super E>> Set<E> copyOf(
      Iterator<? extends E> elements);

  private final ImmutableSet<TestOption> options;

  private boolean outputStreamOpened;
  private boolean outputStreamClosed;

  public TestByteSink(TestOption... options) {
    this.options = ImmutableSet.copyOf(options);
  }

  byte[] getBytes() {
    return bytes.toByteArray();
  }

  @Override
  public boolean wasStreamOpened() {
    return outputStreamOpened;
  }

  @Override

      return parameterizedTable;
    } else {
      return copyOf(table.cellSet());
    }
  }

  static <R, C, V> ImmutableTable<R, C, V> copyOf(
      Iterable<? extends Cell<? extends R, ? extends C, ? extends V>> cells) {
    ImmutableTable.Builder<R, C, V> builder = ImmutableTable.builder();
    for (Cell<? extends R, ? extends C, ? extends V> cell : cells) {

  }

  @Test
  public void copyOfImmutableNetwork_optimized() {
    Network<String, String> network1 =
        ImmutableNetwork.copyOf(NetworkBuilder.directed().<String, String>build());
    Network<String, String> network2 = ImmutableNetwork.copyOf(network1);

    assertThat(network2).isSameInstanceAs(network1);
  }

  @Test
  public void edgesConnecting_directed() {

      @Override
      public <E extends Comparable<E>> Set<E> create(Collection<E> contents) {
        return ImmutableSet.copyOf(contents);
      }
    },
    ImmutableSortedSetImpl {
      @Override
      public <E extends Comparable<E>> Set<E> create(Collection<E> contents) {
        return ImmutableSortedSet.copyOf(contents);
      }
    },
    ContiguousSetImpl {
      @Override

      return ImmutableSortedSet.copyOf(elements);
    }
  }

  public static class ImmutableSortedSetHeadsetGenerator extends TestStringSortedSetGenerator {
    @Override
    protected SortedSet<String> create(String[] elements) {
      List<String> list = Lists.newArrayList(elements);
      list.add("zzz");
      return ImmutableSortedSet.copyOf(list).headSet("zzy");
    }
  }

    ImmutableList.Builder<List<E>> axesBuilder = new ImmutableList.Builder<>(lists.size());
    for (List<? extends E> list : lists) {
      List<E> copy = ImmutableList.copyOf(list);
      if (copy.isEmpty()) {
        return ImmutableList.of();
      }
      axesBuilder.add(copy);
    }
    return new CartesianList<>(axesBuilder.build());
  }

  CartesianList(ImmutableList<List<E>> axes) {
    this.axes = axes;