@Override
    public void addFirst(E e) {
      synchronized (mutex) {
        delegate().addFirst(e);
      }
    }

    @Override
    public void addLast(E e) {
      synchronized (mutex) {
        delegate().addLast(e);
      }
    }

    @Override
    public boolean offerFirst(E e) {
      synchronized (mutex) {
        return delegate().offerFirst(e);
      }
    }

    @Override
    public void addFirst(E e) {
      synchronized (mutex) {
        delegate().addFirst(e);
      }
    }

    @Override
    public void addLast(E e) {
      synchronized (mutex) {
        delegate().addLast(e);
      }
    }

    @Override
    public boolean offerFirst(E e) {
      synchronized (mutex) {
        return delegate().offerFirst(e);
      }
    }

	public final fun addFormDataPart (Ljava/lang/String;Ljava/lang/String;Lokhttp3/RequestBody;)Lokhttp3/MultipartBody$Builder;
	public final fun addPart (Lokhttp3/Headers;Lokhttp3/RequestBody;)Lokhttp3/MultipartBody$Builder;
	public final fun addPart (Lokhttp3/MultipartBody$Part;)Lokhttp3/MultipartBody$Builder;
	public final fun addPart (Lokhttp3/RequestBody;)Lokhttp3/MultipartBody$Builder;
	public final fun build ()Lokhttp3/MultipartBody;

public class IteratorsTest extends TestCase {

  @J2ktIncompatible
  @GwtIncompatible // suite
  public static Test suite() {
    TestSuite suite = new TestSuite(IteratorsTest.class.getSimpleName());
    suite.addTest(testsForRemoveAllAndRetainAll());
    suite.addTestSuite(IteratorsTest.class);
    return suite;
  }

  @SuppressWarnings("DoNotCall")
  public void testEmptyIterator() {

public class IteratorsTest extends TestCase {

  @J2ktIncompatible
  @GwtIncompatible // suite
  public static Test suite() {
    TestSuite suite = new TestSuite(IteratorsTest.class.getSimpleName());
    suite.addTest(testsForRemoveAllAndRetainAll());
    suite.addTestSuite(IteratorsTest.class);
    return suite;
  }

  @SuppressWarnings("DoNotCall")
  public void testEmptyIterator() {