StandardMutableGraph(AbstractGraphBuilder<? super N> builder) {
    this.backingValueGraph = new StandardMutableValueGraph<>(builder);
  }

  @Override
  BaseGraph<N> delegate() {
    return backingValueGraph;
  }

  @Override
  public boolean addNode(N node) {
    return backingValueGraph.addNode(node);
  }

  @Override
  public boolean putEdge(N nodeU, N nodeV) {

  }

  private inner class DelayedRequestBody(
    private val delegate: RequestBody,
    delay: Long,
    timeUnit: TimeUnit,
  ) : RequestBody() {
    private val delayMillis = timeUnit.toMillis(delay)

    override fun contentType() = delegate.contentType()

    override fun isDuplex() = true

    override fun writeTo(sink: BufferedSink) {

    out.write(b);
    count++;
  }

  // Overriding close() because FilterOutputStream's close() method pre-JDK8 has bad behavior:
  // it silently ignores any exception thrown by flush(). Instead, just close the delegate stream.
  // It should flush itself if necessary.
  @Override
  public void close() throws IOException {
    out.close();
  }

#define TENSORFLOW_C_EAGER_GRADIENTS_INTERNAL_H_

#include "tensorflow/c/eager/gradients.h"

namespace tensorflow {
namespace gradients {
namespace internal {

// Helper functions which delegate to `AbstractOperation`, update
// the state of the ForwardOperation and call the tape as appropriate.
// These APIs are mainly to facilitate testing and are subject to change.

// Records the op name in the `ForwardOperation`.

              @Override
              public SortedSet<String> create(String[] elements) {
                NavigableSet<String> delegate = new TreeSet<>(MinimalCollection.of(elements));
                return Collections.synchronizedNavigableSet(delegate);
              }
            })
        .named("synchronizedNavigableSet/TreeSet, natural")
        .withFeatures(
            SetFeature.GENERAL_PURPOSE,

                    byAscendingSize, startIndex, inputIsSet),
                e);
          }
          /*
           * TODO(cpovirk): Check that the values match one of candidates that
           * MutatedOnQuery*.delegate() actually returned during this test?
           */
          assertWithMessage(
                  "byAscendingSize %s, startIndex %s, inputIsSet %s",
                  byAscendingSize, startIndex, inputIsSet)

  }

  public void testPadEnd_null() {
    assertThrows(NullPointerException.class, () -> Strings.padEnd(null, 5, '0'));
  }

  @SuppressWarnings("InlineMeInliner") // test of method that doesn't just delegate
  public void testRepeat() {
    String input = "20";
    assertEquals("", Strings.repeat(input, 0));
    assertEquals("20", Strings.repeat(input, 1));
    assertEquals("2020", Strings.repeat(input, 2));

    return hasher.hash();
  }

  // Overriding close() because FilterOutputStream's close() method pre-JDK8 has bad behavior:
  // it silently ignores any exception thrown by flush(). Instead, just close the delegate stream.
  // It should flush itself if necessary.
  @Override
  public void close() throws IOException {
    out.close();
  }

  private static class BadLengthFile extends File {

    private final long badLength;

    public BadLengthFile(File delegate, long badLength) {
      super(delegate.getPath());
      this.badLength = badLength;
    }

    @Override
    public long length() {
      return badLength;
    }

    private static final long serialVersionUID = 0;

      this.concurrencyLevel = concurrencyLevel;
      this.delegate = delegate;
    }

    @Override
    protected ConcurrentMap<K, V> delegate() {
      return delegate;
    }

    void writeMapTo(ObjectOutputStream out) throws IOException {
      out.writeInt(delegate.size());
      for (Entry<K, V> entry : delegate.entrySet()) {
        out.writeObject(entry.getKey());