class UnicornException(Exception):
    def __init__(self, name: str):
        self.name = name


app = FastAPI()


@app.exception_handler(UnicornException)
async def unicorn_exception_handler(request: Request, exc: UnicornException):
    return JSONResponse(
        status_code=418,
        content={"message": f"Oops! {exc.name} did something. There goes a rainbow..."},
    )

{* ../../docs_src/handling_errors/tutorial003_py39.py hl[5:7,13:18,24] *}

Здесь, если запросить `/unicorns/yolo`, то *операция пути* вызовет `UnicornException`.

Но оно будет обработано `unicorn_exception_handler`.

Таким образом, вы получите чистую ошибку с кодом состояния HTTP `418` и содержимым JSON:

```JSON
{"message": "Oops! yolo did something. There goes a rainbow..."}
```

{* ../../docs_src/handling_errors/tutorial003_py39.py hl[5:7,13:18,24] *}

Hier, wenn Sie `/unicorns/yolo` anfordern, wird die *Pfadoperation* eine `UnicornException` `raise`n.

Aber diese wird von `unicorn_exception_handler` gehandhabt.

Sie erhalten also einen sauberen Fehler mit einem HTTP-Statuscode von `418` und dem JSON-Inhalt:

```JSON
{"message": "Oops! yolo did something. There goes a rainbow..."}
```

{* ../../docs_src/handling_errors/tutorial003_py39.py hl[5:7,13:18,24] *}

Here, if you request `/unicorns/yolo`, the *path operation* will `raise` a `UnicornException`.

But it will be handled by the `unicorn_exception_handler`.

So, you will receive a clean error, with an HTTP status code of `418` and a JSON content of:

```JSON
{"message": "Oops! yolo did something. There goes a rainbow..."}
```

Nesse cenário, se você fizer uma requisição para `/unicorns/yolo`, a *operação de caminho* vai lançar (`raise`) o `UnicornException`.

Essa exceção será manipulada, contudo, pelo `unicorn_exception_handler`.

Dessa forma você receberá um erro "limpo", com o HTTP status code `418` e um JSON com o conteúdo:

```JSON
{"message": "Oops! yolo did something. There goes a rainbow..."}
```

{* ../../docs_src/handling_errors/tutorial003_py39.py hl[5:7,13:18,24] *}

Aquí, si solicitas `/unicorns/yolo`, la *path operation* lanzará un `UnicornException`.

Pero será manejado por el `unicorn_exception_handler`.

Así que recibirás un error limpio, con un código de estado HTTP de `418` y un contenido JSON de:

```JSON
{"message": "Oops! yolo did something. There goes a rainbow..."}
```

            def __init__(self, name: str):
                self.name = name


        app = FastAPI()


        @app.exception_handler(UnicornException)
        async def unicorn_exception_handler(request: Request, exc: UnicornException):
            return JSONResponse(
                status_code=418,
                content={"message": f"Oops! {exc.name} did something. There goes a rainbow..."},