```Python
q: str
```

à la place de :

```Python
q: Union[str, None] = None
```

Mais maintenant, on déclare `q` avec `Query`, comme ceci :

```Python
q: Union[str, None] = Query(default=None, min_length=3)
```

//// tab | Python 3.10+

```Python hl_lines="7  48  55-56  59-60  69-75"
{!> ../../docs_src/security/tutorial004_an_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="7  48  55-56  59-60  69-75"
{!> ../../docs_src/security/tutorial004_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="7  49  56-57  60-61  70-76"

## Імпорт `Field`

Спочатку вам потрібно імпортувати це:

//// tab | Python 3.10+

```Python hl_lines="4"
{!> ../../docs_src/body_fields/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="4"
{!> ../../docs_src/body_fields/tutorial001_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="4"
{!> ../../docs_src/body_fields/tutorial001_an.py!}
```

```

そして呼び出すと:

```Python
user_dict = user_in.dict()
```

これで変数`user_dict`のデータを持つ`dict`ができました。（これはPydanticモデルのオブジェクトの代わりに`dict`です）。

そして呼び出すと:

```Python
print(user_dict)
```

以下のようなPythonの`dict`を得ることができます:

```Python
{
    'username': 'john',
    'password': 'secret',
    'email': '******@****.***',
    'full_name': None,
}
```

#### `dict`の展開

//// tab | Python 3.10+

```Python hl_lines="1  3  12-16"
{!> ../../docs_src/extra_data_types/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="1  3  12-16"
{!> ../../docs_src/extra_data_types/tutorial001_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="1  3  13-17"

Она принимает объект, например, модель Pydantic, и возвращает его версию, совместимую с JSON:

//// tab | Python 3.10+

```Python hl_lines="4  21"
{!> ../../docs_src/encoder/tutorial001_py310.py!}
```

////

//// tab | Python 3.6+

```Python hl_lines="5  22"
{!> ../../docs_src/encoder/tutorial001.py!}
```

////

//// tab | Python 3.10+

```Python hl_lines="9"
{!> ../../docs_src/dependencies/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="11"
{!> ../../docs_src/dependencies/tutorial001_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="12"
{!> ../../docs_src/dependencies/tutorial001_an.py!}
```

//// tab | Python 3.10+

```Python hl_lines="9"
{!> ../../docs_src/dependencies/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="11"
{!> ../../docs_src/dependencies/tutorial001_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="12"
{!> ../../docs_src/dependencies/tutorial001_an.py!}
```

Z. B. `pip install python-multipart`.

///

## `File` und `Form` importieren

//// tab | Python 3.9+

```Python hl_lines="3"
{!> ../../docs_src/request_forms_and_files/tutorial001_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="1"

* 返回类型为 `HTTPBasicCredentials` 的对象：
    * 包含发送的 `username` 与 `password`

//// tab | Python 3.9+

```Python hl_lines="4  8  12"
{!> ../../docs_src/security/tutorial006_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="2  7  11"
{!> ../../docs_src/security/tutorial006_an.py!}
```

////

//// tab | Python 3.8+ non-Annotated

/// tip

尽可能选择使用 `Annotated` 的版本。

///