* propagating it.
   *
   * <p>While it's not safe in the general case to ignore exceptions that are thrown when closing an
   * I/O resource, it should generally be safe in the case of a resource that's being used only for
   * reading, such as an {@code InputStream}. Unlike with writable resources, there's no chance that
   * a failure that occurs when closing the stream indicates a meaningful problem such as a failure

@SuppressWarnings("serial") // No serialization is used in this test
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class PeekingIteratorTest extends TestCase {

  /**
   * Version of {@link IteratorTester} that compares an iterator over a given collection of elements
   * (used as the reference iterator) against a {@code PeekingIterator} that *wraps* such an
   * iterator (used as the target iterator).
   *

 *  New: `Request.Builder.cacheUrlOverride()` customizes the cache key used for a request. This can
    be used to make canonical URLs for the cache that omit insignificant query parameters or other
    irrelevant data.

    This feature may be used with `POST` requests to cache their responses. In such cases the
    request body is not used to determine the cache key, so you must manually add cache-relevant

    return burgers
```

### Mais detalhes técnicos

Você deve ter observado que `await` pode ser usado somente dentro de funções definidas com `async def`.

Mas ao mesmo tempo, funções definidas com `async def` tem que ser aguardadas. Então, funções com `async def` pdem ser chamadas somente dentro de funções definidas com `async def` também.

Então, sobre o ovo e a galinha, como você chama a primeira função async?

# Testando WebSockets

Você pode usar o mesmo `TestClient` para testar WebSockets.

Para isso, você utiliza o `TestClient` dentro de uma instrução `with`, conectando com o WebSocket:

```Python hl_lines="27-31"
{!../../docs_src/app_testing/tutorial002.py!}
```

/// note | "Nota"

     * @param request The model building request that holds further settings, must not be {@code null}.
     * @param problems The container used to collect problems that were encountered, must not be {@code null}.
     */
    void expandPluginConfiguration(Model model, ModelBuildingRequest request, ModelProblemCollector problems);

DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

If you want something quick to copy and paste, don't use this example, use the last one below.

///

Then, when you create an instance of that `Settings` class (in this case, in the `settings` object), Pydantic will read the environment variables in a case-insensitive way, so, an upper-case variable `APP_NAME` will still be read for the attribute `app_name`.

SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.