```Python hl_lines="30-31" title="app/routers/items.py"
{!../../docs_src/bigger_applications/app/routers/items.py!}
```

/// tip

This last path operation will have the combination of tags: `["items", "custom"]`.

And it will also have both responses in the documentation, one for `404` and one for `403`.

///

## The main `FastAPI` { #the-main-fastapi }

<div class="termy">

```console
$ cd ~/code/prisoner-of-azkaban

$ python main.py

// Error importing sirius, it's not installed 😱
Traceback (most recent call last):
    File "main.py", line 1, in <module>
        import sirius
```

</div>

    --hash=sha256:8dbdec58f935f3765e4f7f3cf635ac3a77f83568138d6a2311f524ec96364812 \
    --hash=sha256:de2ec5b203f21441716617f38443e0a8ebf3d25bf0d9c0bb0ce68fa00ad546a4
    # via -r ci/official/requirements_updater/requirements.in
gast==0.4.0 \
    --hash=sha256:40feb7b8b8434785585ab224d1568b857edb18297e5a3047f1ba012bc83b42c1 \
    --hash=sha256:b7adcdd5adbebf1adf17378da5ba3f543684dbec47b1cda1f3997e573cd542c4

    --hash=sha256:8dbdec58f935f3765e4f7f3cf635ac3a77f83568138d6a2311f524ec96364812 \
    --hash=sha256:de2ec5b203f21441716617f38443e0a8ebf3d25bf0d9c0bb0ce68fa00ad546a4
    # via -r ci/official/requirements_updater/requirements.in
gast==0.4.0 \
    --hash=sha256:40feb7b8b8434785585ab224d1568b857edb18297e5a3047f1ba012bc83b42c1 \
    --hash=sha256:b7adcdd5adbebf1adf17378da5ba3f543684dbec47b1cda1f3997e573cd542c4

    --hash=sha256:8dbdec58f935f3765e4f7f3cf635ac3a77f83568138d6a2311f524ec96364812 \
    --hash=sha256:de2ec5b203f21441716617f38443e0a8ebf3d25bf0d9c0bb0ce68fa00ad546a4
    # via -r ci/official/requirements_updater/requirements.in
gast==0.4.0 \
    --hash=sha256:40feb7b8b8434785585ab224d1568b857edb18297e5a3047f1ba012bc83b42c1 \
    --hash=sha256:b7adcdd5adbebf1adf17378da5ba3f543684dbec47b1cda1f3997e573cd542c4

   * value}.
   *
   * @param value any {@code long} value
   * @return {@code 2^32 - 1} if {@code value >= 2^32}, {@code 0} if {@code value <= 0}, and {@code
   *     value} cast to {@code int} otherwise
   * @since 21.0
   */
  public static int saturatedCast(long value) {
    if (value <= 0) {
      return 0;
    } else if (value >= (1L << 32)) {
      return -1;
    } else {

* `filename` - Se for definido, é incluído no cabeçalho `Content-Disposition`.

Respostas de Arquivos incluem o tamanho do arquivo, data da última modificação e ETags apropriados, nos cabeçalhos `Content-Length`, `Last-Modified` e `ETag`, respectivamente.

{* ../../docs_src/custom_response/tutorial009.py hl[2,10] *}

Você também pode usar o parâmetro `response_class`:

{* ../../docs_src/custom_response/tutorial009b.py hl[2,8,10] *}

     * <p>
     * If the object is null, an empty list is returned.
     * If the object is a string, a list containing that string is returned.
     * If the object is a list, it is cast to a list of strings and returned.
     * </p>
     *
     * @param value the object to be converted to a list of strings
     * @return a list of strings representing the given object

     * `ID > lastGoodStreamId` on a new connection.  In- flight streams with
     * `ID <= lastGoodStreamId` can only be replayed on a new connection if they are idempotent.
     *
     * @param lastGoodStreamId the last stream ID the peer processed before sending this message. If
     *     [lastGoodStreamId] is zero, the peer processed no frames.
     * @param errorCode reason for closing the connection.

   * the provided key, an empty immutable list is returned. The values are in the same order as the
   * parameters used to build this multimap.
   */
  @Override
  public ImmutableList<V> get(K key) {
    // This cast is safe as its type is known in constructor.
    ImmutableList<V> list = (ImmutableList<V>) map.get(key);
    return (list == null) ? ImmutableList.<V>of() : list;
  }