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

Ou bien, en Python 3.10 et supérieur :

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

Par exemple :

{* ../../docs_src/body_multiple_params/tutorial004_an_py310.py hl[27] *}

/// info

`@lru_cache` es parte de `functools`, que es parte del paquete estándar de Python, puedes leer más sobre él en las <a href="https://docs.python.org/3/library/functools.html#functools.lru_cache" class="external-link" target="_blank">docs de Python para `@lru_cache`</a>.

## Resumen { #recap }

load(
    "//tensorflow/python/tools/api/generator:api_gen.bzl",
    "get_compat_files",
    "get_nested_compat_files",
)
load(
    "//tensorflow/python/tools/api/generator:api_init_files.bzl",
    "TENSORFLOW_API_INIT_FILES",
)
load(
    "//tensorflow/python/tools/api/generator:api_init_files_v1.bzl",
    "TENSORFLOW_API_INIT_FILES_V1",
)

needs_py39 = pytest.mark.skipif(sys.version_info < (3, 9), reason="requires python3.9+")
needs_py310 = pytest.mark.skipif(
    sys.version_info < (3, 10), reason="requires python3.10+"
)
needs_py_lt_314 = pytest.mark.skipif(
    sys.version_info >= (3, 14), reason="requires python3.13-"
)


def skip_module_if_py_gte_314():
    """Skip entire module on Python 3.14+ at import time."""
    if sys.version_info >= (3, 14):

Um Formulare zu verwenden, installieren Sie zuerst <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Stellen Sie sicher, dass Sie eine [virtuelle Umgebung](../virtual-environments.md){.internal-link target=_blank} erstellen, sie aktivieren und es dann installieren, zum Beispiel:

```console
$ pip install python-multipart
```

///

/// note | Hinweis

這一點，再加上 Python 是 **資料科學**、機器學習，尤其是深度學習的主要語言，讓 **FastAPI** 成為資料科學/機器學習 Web API 和應用程式（以及許多其他應用程式）的絕佳選擇。

想了解如何在生產環境中實現這種平行性，請參見 [部屬](deployment/index.md){.internal-link target=_blank}。

## `async` 和 `await`

現代 Python 版本提供一種非常直觀的方式定義非同步程式碼。這使得它看起來就像正常的「順序」程式碼，並在適當的時機「等待」。

當某個操作需要等待才能回傳結果，並且支援這些新的 Python 特性時，你可以像這樣編寫程式碼：

```Python
burgers = await get_burgers(2)
```

/// note | Hinweis

FastAPI weiß, dass der Wert von `q` nicht erforderlich ist, aufgrund des definierten Defaultwertes `= None`.

Das `str | None` (Python 3.10+) oder `Union` in `Union[str, None]` (Python 3.9+) wird von FastAPI nicht verwendet, um zu bestimmen, dass der Wert nicht erforderlich ist. FastAPI weiß, dass er nicht erforderlich ist, weil er einen Defaultwert von `= None` hat.

    ],
)

# -----------------------------------------------------------------------------
# Python API target

tf_cuda_library(
    name = "python_api",
    srcs = ["python_api.cc"],
    hdrs = ["python_api.h"],
    visibility = [
        "//tensorflow:internal",
        "//tensorflow/python:__pkg__",
    ],
    deps = [
        ":c_api",
        ":c_api_internal",

#!/usr/bin/env bash

set -e
set -o pipefail

if [ -z "$PYTHON_BIN_PATH" ]; then
  PYTHON_BIN_PATH=$(which python3 || which python || true)
fi

# Set all env variables
CONFIGURE_DIR=$(dirname "$0")
"$PYTHON_BIN_PATH" "${CONFIGURE_DIR}/configure.py" "$@"

## `Depends()`

Dependencies are handled mainly with the special function `Depends()` that takes a callable.

Here is the reference for it and its parameters.

You can import it directly from `fastapi`:

```python
from fastapi import Depends
```

::: fastapi.Depends

## `Security()`

For many scenarios, you can handle security (authorization, authentication, etc.) with dependencies, using `Depends()`.