/**
 * A map which forwards all its method calls to another map. Subclasses should override one or more
 * methods to modify the behavior of the backing map as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingMap} forward <i>indiscriminately</i> to the
 * methods of the delegate. For example, overriding {@link #put} alone <i>will not</i> change the

 * den Pfad `/`
 * unter der Verwendung der <abbr title="eine HTTP GET Methode"><code>get</code>-Operation</abbr> gehen

/// info | "`@decorator` Information"

Diese `@something`-Syntax wird in Python „Dekorator“ genannt.

Sie platzieren ihn über einer Funktion. Wie ein hübscher, dekorativer Hut (daher kommt wohl der Begriff).

* **Uitbreidbaar**:
    * Met Pydantic kunnen op maat gemaakte datatypen worden gedefinieerd of je kunt validatie uitbreiden met methoden op een model dat is ingericht met de decorator validator.

 * one or more methods to modify the behavior of the backing multiset as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingMultiset} forward <b>indiscriminately</b> to
 * the methods of the delegate. For example, overriding {@link #add(Object, int)} alone <b>will

That's it.

**2 lines**.

And it has the same shape and structure that all your *path operation functions* have.

You can think of it as a *path operation function* without the "decorator" (without the `@app.get("/some-path")`).

And it can return anything you want.

In this case, this dependency expects:

* An optional query parameter `q` that is a `str`.

Lo importante es que usando los tipos de Python estándar en un único lugar (en vez de añadir más clases, decorator, etc.) **FastAPI** hará mucho del trabajo por ti.

/// info | Información

                  "max_stream_duration": {
                   "max_stream_duration": "0s",
                   "grpc_timeout_header_max": "0s"
                  }
                 },
                 "decorator": {
                  "operation": ":0/*"
                 },
                 "name": "default"
                }
               ]
              }
             ],

* **قابل توسعه**:
    * Pydantic اجازه میدهد تا data type های سفارشی تعریف شوند یا میتوانید اعتبارسنجی را با روش هایی به روی مدل ها با <abbr title="دکوریتور های اعتبارسنج">validator decorator</abbr> گسترش دهید.

Quando a requisição contém dados inválidos, **FastAPI** internamente lança para o `RequestValidationError`.

Para sobrescrevê-lo, importe o `RequestValidationError` e use-o com o `@app.exception_handler(RequestValidationError)` para decorar o manipulador de exceções.

```Python hl_lines="2  14-16"
{!../../docs_src/handling_errors/tutorial004.py!}
```

Se você for ao `/items/foo`, em vez de receber o JSON padrão com o erro:

```JSON
{

### Concurrence et Burgers

L'idée de code **asynchrone** décrite ci-dessus est parfois aussi appelée **"concurrence"**. Ce qui est différent du **"parallélisme"**.

La **concurrence** et le **parallélisme** sont tous deux liés à l'idée de "différentes choses arrivant plus ou moins au même moment".