public int size() {
    return 1;
  }

  @Override
  public boolean contains(@Nullable Object target) {
    return element.equals(target);
  }

  @Override
  public UnmodifiableIterator<E> iterator() {
    return singletonIterator(element);
  }

  @Override
  public ImmutableList<E> asList() {
    return ImmutableList.of(element);
  }

  @Override
  boolean isPartialView() {
    return false;

---

Por ejemplo, en Visual Studio Code, puedes:

* Ir al panel de "Debug".
* "Add configuration...".
* Seleccionar "Python".
* Ejecutar el depurador con la opción "`Python: Current File (Integrated Terminal)`".

Luego, iniciará el servidor con tu código **FastAPI**, deteniéndose en tus puntos de interrupción, etc.

Así es como podría verse:

<img src="/img/tutorial/debugging/image01.png">

---

  fun assertJobs(vararg expectedUrls: String) {
    val actualUrls = calls.map { it.request.url.toString() }
    assertThat(actualUrls).containsExactly(*expectedUrls)
  }

  fun finishJob(url: String) {
    val i = calls.iterator()
    while (i.hasNext()) {
      val call = i.next()
      if (call.request.url.toString() == url) {
        i.remove()
        dispatcherTest.dispatcher.finishedAccessor(call)
        return
      }
    }

        return ImmutableMultiset.copyOf(keys);
      }
    },
    COPY_OF_ITERATOR {
      @Override
      public ImmutableMultiset<Object> create(List<?> keys) {
        return ImmutableMultiset.copyOf(keys.iterator());
      }
    },
    BUILDER_ADD_ENTRY_BY_ENTRY {
      @Override
      public ImmutableMultiset<Object> create(List<?> keys) {
        ImmutableMultiset.Builder<Object> builder = ImmutableMultiset.builder();

    cache.evictAll()
  }

  /**
   * Returns an iterator over the URLs in this cache. This iterator doesn't throw
   * `ConcurrentModificationException`, but if new responses are added while iterating, their URLs
   * will not be returned. If existing responses are evicted during iteration, they will be absent
   * (unless they were already returned).
   *

///

/// info

In this example we use invented custom headers `X-Key` and `X-Token`.

But in real cases, when implementing security, you would get more benefits from using the integrated [Security utilities (the next chapter)](../security/index.md){.internal-link target=_blank}.

///

## Dependencies errors and return values { #dependencies-errors-and-return-values }

비동기 제너레이터 또는 일반 제너레이터/이터레이터를 받아 응답 본문을 스트리밍 합니다.

{* ../../docs_src/custom_response/tutorial007.py hl[2,14] *}

#### 파일과 같은 객체를 사용한 `StreamingResponse`

파일과 같은 객체(예: `open()`으로 반환된 객체)가 있는 경우, 해당 파일과 같은 객체를 반복(iterate)하는 제너레이터 함수를 만들 수 있습니다.

이 방식으로, 파일 전체를 메모리에 먼저 읽어들일 필요 없이, 제너레이터 함수를 `StreamingResponse`에 전달하여 반환할 수 있습니다.

이 방식은 클라우드 스토리지, 비디오 처리 등의 다양한 라이브러리와 함께 사용할 수 있습니다.

  // Views

  /**
   * Returns a view of the {@linkplain Range#isConnected disconnected} ranges that make up this
   * range set. The returned set may be empty. The iterators returned by its {@link
   * Iterable#iterator} method return the ranges in increasing order of lower bound (equivalently,
   * of upper bound).
   */
  Set<Range<C>> asRanges();

  /**

    assertThat(ArbitraryInstances.get(UUID.class)).isNotNull();
  }

  public void testGet_collections() {
    assertEquals(ImmutableSet.of().iterator(), ArbitraryInstances.get(Iterator.class));
    assertFalse(ArbitraryInstances.get(PeekingIterator.class).hasNext());
    assertFalse(ArbitraryInstances.get(ListIterator.class).hasNext());

  static void checkPositive(int value, String name) {
    if (value <= 0) {
      throw new IllegalArgumentException(name + " must be positive but was: " + value);
    }
  }

  /**
   * Precondition tester for {@code Iterator.remove()} that throws an exception with a consistent
   * error message.
   */
  static void checkRemove(boolean canRemove) {
    checkState(canRemove, "no calls to next() since the last call to remove()");
  }