assertThrows(
        ConcurrentModificationException.class,
        () -> {
          Iterator<Entry<K, V>> iterator = getMap().entrySet().iterator();
          getMap().remove(k0());
          iterator.next();
        });
  }

  @MapFeature.Require({FAILS_FAST_ON_CONCURRENT_MODIFICATION, SUPPORTS_REMOVE})
  @CollectionSize.Require(SEVERAL)
  public void testRemovePresentConcurrentWithKeySetIteration() {
    assertThrows(

  }

  private Entry<K, V> getEntryNullReplaces() {
    Iterator<Entry<K, V>> entries = getSampleElements().iterator();
    for (int i = 0; i < getNullLocation(); i++) {
      entries.next();
    }
    return entries.next();
  }

  /**
   * @return an array of the proper size with {@code null} as the value of the middle element.
   */
  protected Entry<K, V>[] createArrayWithNullValue() {

  @Override
  public final boolean hasNext() {
    return backingIterator.hasNext();
  }

  @Override
  @ParametricNullness
  public final T next() {
    return transform(backingIterator.next());
  }

  @Override
  public final void remove() {
    backingIterator.remove();
  }

  }

  @CollectionFeature.Require({SUPPORTS_ADD, FAILS_FAST_ON_CONCURRENT_MODIFICATION})
  public void testSetCountZeroToOneConcurrentWithEntrySetIteration() {
    Iterator<Entry<E>> iterator = getMultiset().entrySet().iterator();
    assertSetCount(e3(), 1);
    assertThrows(ConcurrentModificationException.class, iterator::next);
  }

    }

    @Override
    public boolean hasNext() {
      return !stack.isEmpty();
    }

    @Override
    public T next() {
      Iterator<T> itr = stack.getLast(); // throws NSEE if empty
      T result = checkNotNull(itr.next());
      if (!itr.hasNext()) {
        stack.removeLast();
      }
      Iterator<T> childItr = children(result).iterator();
      if (childItr.hasNext()) {

### `response_model` ou Tipo de Retorno

Neste caso, como os dois modelos são diferentes, se anotássemos o tipo de retorno da função como `UserOut`, o editor e as ferramentas reclamariam que estamos retornando um tipo inválido, pois são classes diferentes.

É por isso que neste exemplo temos que declará-lo no parâmetro `response_model`.

                final CommonServerMessageBlockRequest next = chain.getNext();
                if (log.isTraceEnabled()) {
                    log.trace(String.format("%s costs %d avail %d (%s)", chain.getClass().getName(), cost, this.credits.availablePermits(),
                            this.name));
                }
                if ((next == null || chain.allowChain(next)) && totalSize + size < maxSize && this.credits.tryAcquire(cost)) {

      protected @Nullable C computeNext() {
        while (merged.hasNext()) {
          C next = merged.next();
          boolean duplicate = lastValue != null && comparator.compare(next, lastValue) == 0;

          // Keep looping till we find a non-duplicate value.
          if (!duplicate) {
            lastValue = next;
            return lastValue;
          }
        }

    assertThrows(NoSuchElementException.class, empty::next);
    assertThrows(UnsupportedOperationException.class, empty::remove);
  }

  public void testBroken() {
    Iterator<Object> broken = new BrokenAbstractSequentialIterator();
    assertTrue(broken.hasNext());
    // We can't retrieve even the known first element:
    assertThrows(SomeUncheckedException.class, broken::next);

    assertThrows(
        ConcurrentModificationException.class,
        () -> {
          Iterator<Entry<K, V>> iterator = getMap().entrySet().iterator();
          getMap().clear();
          iterator.next();
        });
  }

  @MapFeature.Require({FAILS_FAST_ON_CONCURRENT_MODIFICATION, SUPPORTS_REMOVE})
  @CollectionSize.Require(SEVERAL)
  public void testClearConcurrentWithKeySetIteration() {
    assertThrows(