For this, use the Python standard module <a href="https://docs.python.org/3/library/secrets.html" class="external-link" target="_blank">`secrets`</a> to check the username and password.

`secrets.compare_digest()` needs to take `bytes` or a `str` that only contains ASCII characters (the ones in English), this means it wouldn't work with characters like `á`, as in `Sebastián`.

To handle that, we first convert the `username` and `password` to `bytes` encoding them with UTF-8.

В нашем случае это `str`:

```Python
"{$callback_url}/invoices/{$request.body.id}"
```

Итак, если пользователь вашего API (внешний разработчик) отправляет HTTP-запрос вашему API по адресу:

```

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Optional[str] = None):
    return {"item_id": item_id, "q": q}
```

* Vous devriez maintenant avoir une structure de répertoire telle que :

```
.
├── app
│   └── main.py
└── Dockerfile
```

   *     Stream.of("banana", "apple", "carrot", "asparagus", "cherry")
   *         .collect(
   *             toMultimap(
   *                  str -> str.charAt(0),
   *                  str -> str.substring(1),
   *                  MultimapBuilder.treeKeys().arrayListValues()::build));
   *
   * // is equivalent to
   *
   * static final ListMultimap<Character, String> FIRST_LETTER_MULTIMAP;

```JSON
{
  "detail": "Item not found"
}
```

/// tip | Подсказка

При вызове `HTTPException` в качестве параметра `detail` можно передавать любое значение, которое может быть преобразовано в JSON, а не только `str`.

Вы можете передать `dict`, `list` и т.д.

Они автоматически обрабатываются **FastAPI** и преобразуются в JSON.

///

## Добавление пользовательских заголовков { #add-custom-headers }

기본적으로 단일 값은 쿼리 매개변수로 해석되므로, 명시적으로 `Query`를 추가할 필요가 없고, 아래처럼 할 수 있습니다:

{* ../../docs_src/body_multiple_params/tutorial004.py hl[27] *}

이렇게:

```Python
q: Optional[str] = None
```

/// info | 정보

`Body` 또한 `Query`, `Path` 그리고 이후에 볼 다른 것들처럼 동일한 추가 검증과 메타데이터 매개변수를 갖고 있습니다.

///

## 단일 본문 매개변수 삽입하기

Pydantic 모델 `Item`의 `item`을 본문 매개변수로 오직 한개만 갖고있다고 하겠습니다.

    }

    /**
     * Abbreviates a long text string.
     *
     * @param str The string to abbreviate.
     * @return The abbreviated string.
     */
    public String abbreviateLongText(final String str) {
        return StringUtils.abbreviate(str, ComponentUtil.getFessConfig().getMaxLogOutputLengthAsInteger());
    }

    /**
     * Normalizes an HTML language string.

// Comparison is case insensitive. Explicit short-circuit if
// the list contains the wildcard "*".
func hasStringSuffixInSlice(str string, list []string) bool {
	str = strings.ToLower(str)
	for _, v := range list {
		if v == "*" {
			return true
		}

		if strings.HasSuffix(str, strings.ToLower(v)) {
			return true
		}
	}
	return false
}

In diesem Fall ist es der `str`:

```Python
"{$callback_url}/invoices/{$request.body.id}"
```

Wenn Ihr API-Benutzer (der externe Entwickler) also einen Request an *Ihre API* sendet, via:

```

That means that **any value** read in Python from an environment variable **will be a `str`**, and any conversion to a different type or any validation has to be done in code.