* Es enthält den gesendeten `username` und das gesendete `password`.

=== "Python 3.9+"

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

=== "Python 3.8+"

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

=== "Python 3.8+ nicht annotiert"

    !!! tip "Tipp"

=== "Python 3.10+"

    ```Python hl_lines="9  17"
    {!> ../../../docs_src/request_files/tutorial001_02_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="9  17"
    {!> ../../../docs_src/request_files/tutorial001_02_an_py39.py!}
    ```

=== "Python 3.6+"

    ```Python hl_lines="10  18"

=== "Python 3.10+"

    ```Python hl_lines="19"
    {!> ../../../docs_src/separate_openapi_schemas/tutorial001_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="21"
    {!> ../../../docs_src/separate_openapi_schemas/tutorial001_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="21"

But if you use the same model as an output, like here:

=== "Python 3.10+"

    ```Python hl_lines="19"
    {!> ../../../docs_src/separate_openapi_schemas/tutorial001_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="21"
    {!> ../../../docs_src/separate_openapi_schemas/tutorial001_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="21"

=== "Python 3.9+"

    ```Python hl_lines="15-16"
    {!> ../../../docs_src/dependencies/tutorial008c_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="14-15"
    {!> ../../../docs_src/dependencies/tutorial008c_an.py!}
    ```

=== "Python 3.8+ non-Annotated"

    !!! tip

    ```

    </div>

### Read env vars in Python

You could also create environment variables outside of Python, in the terminal (or with any other method), and then read them in Python.

For example you could have a file `main.py` with:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

!!! tip

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

Or in Python 3.10 and above:

```Python
q: str | None = None
```

For example:

=== "Python 3.10+"

    ```Python hl_lines="27"
    {!> ../../../docs_src/body_multiple_params/tutorial004_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="27"

## Import `Field`

First, you have to import it:

=== "Python 3.10+"

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

=== "Python 3.9+"

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

=== "Python 3.8+"

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

## 导入 `Field`

首先，从 Pydantic 中导入 `Field`：

=== "Python 3.10+"

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

=== "Python 3.9+"

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

=== "Python 3.8+"

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

    {!> ../../../docs_src/dependencies/tutorial006.py!}
    ```

### 오류 발생시키기

다음 의존성은 기존 의존성과 동일하게 예외를 `raise`를 일으킬 수 있습니다:

=== "Python 3.9+"

    ```Python hl_lines="10  15"
    {!> ../../../docs_src/dependencies/tutorial006_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="9  14"
    {!> ../../../docs_src/dependencies/tutorial006_an.py!}
    ```