transferKind.setBody(mockResponse2, "LMNOPQRSTUV", 1024)
    server.enqueue(mockResponse2.build())
    val call1 = client.newCall(newRequest("/"))
    val response1 = call1.execute()
    val in1 = response1.body.byteStream()
    assertThat(readAscii(in1, 5)).isEqualTo("ABCDE")
    in1.close()
    call1.cancel()
    val call2 = client.newCall(newRequest("/"))
    val response2 = call2.execute()

    *   Add support for passing list of lists to the `metrics` argument in Keras
        `compile`.
    *   Add `tf.keras.layers.AbstractRNNCell` as the preferred implementation
        for RNN cells in TF v2. User can use it to implement RNN cells with
        custom behavior.
    *   Keras training and validation curves are shown on the same plot when
        using the TensorBoard callback.

    public Map<R, V> column(@ParametricNullness C columnKey) {
      synchronized (mutex) {
        return map(delegate().column(columnKey), mutex);
      }
    }

    @Override
    public Set<Cell<R, C, V>> cellSet() {
      synchronized (mutex) {
        return set(delegate().cellSet(), mutex);
      }
    }

    @Override
    public Set<R> rowKeySet() {
      synchronized (mutex) {

    public Map<R, V> column(@ParametricNullness C columnKey) {
      synchronized (mutex) {
        return map(delegate().column(columnKey), mutex);
      }
    }

    @Override
    public Set<Cell<R, C, V>> cellSet() {
      synchronized (mutex) {
        return set(delegate().cellSet(), mutex);
      }
    }

    @Override
    public Set<R> rowKeySet() {
      synchronized (mutex) {