async def contextmanager_in_threadpool(
    cm: ContextManager[_T],
) -> AsyncGenerator[_T, None]:
    # blocking __exit__ from running waiting on a free thread
    # can create race conditions/deadlocks if the context manager itself
    # has its own internal pool (e.g. a database connection pool)
    # to avoid this we let __exit__ run without a capacity limit
    # since we're creating a new limiter for each call, any non-zero limit

class MySuperContextManager:
    def __init__(self):
        self.db = DBSession()

    def __enter__(self):
        return self.db

    def __exit__(self, exc_type, exc_value, traceback):
        self.db.close()


async def get_db():
    with MySuperContextManager() as db:

🚥 👆 ▶️ ⏮️ **FastAPI** 👆 💪 💚 🚶 ⚫️ 🔜.

///

🐍, 👆 💪 ✍ 🔑 👨‍💼 <a href="https://docs.python.org/3/reference/datamodel.html#context-managers" class="external-link" target="_blank">🏗 🎓 ⏮️ 2️⃣ 👩‍🔬: `__enter__()` &amp; `__exit__()`</a>.

👆 💪 ⚙️ 👫 🔘 **FastAPI** 🔗 ⏮️ `yield` ⚙️
`with` ⚖️ `async with` 📄 🔘 🔗 🔢:

```Python hl_lines="1-9  13"
{!../../docs_src/dependencies/tutorial010.py!}
```

/// tip

这是一个更为"高级"的想法。

如果你刚开始使用 **FastAPI** ，你可以暂时可以跳过它。

///

在Python中，你可以通过<a href="https://docs.python.org/3/reference/datamodel.html#context-managers" class="external-link" target="_blank">创建一个带有`__enter__()`和`__exit__()`方法的类</a>来创建上下文管理器。

你也可以在 **FastAPI** 的 `yield` 依赖项中通过 `with` 或者 `async with` 语句来使用它们：

```Python hl_lines="1-9  13"
{!../../docs_src/dependencies/tutorial010.py!}
```

/// tip | 提示

///

In Python können Sie Kontextmanager erstellen, indem Sie <a href="https://docs.python.org/3/reference/datamodel.html#context-managers" class="external-link" target="_blank">eine Klasse mit zwei Methoden erzeugen: `__enter__()` und `__exit__()`</a>.

Sie können solche auch innerhalb von **FastAPI**-Abhängigkeiten mit `yield` verwenden, indem Sie `with`- oder `async with`-Anweisungen innerhalb der Abhängigkeits-Funktion verwenden:

```Python hl_lines="1-9  13"

///

In Python, you can create Context Managers by <a href="https://docs.python.org/3/reference/datamodel.html#context-managers" class="external-link" target="_blank">creating a class with two methods: `__enter__()` and `__exit__()`</a>.

You can also use them inside of **FastAPI** dependencies with `yield` by using
`with` or `async with` statements inside of the dependency function:

```Python hl_lines="1-9  13"

**FastAPI** を使い始めたばかりの方は、とりあえずスキップした方がよいかもしれません。

///

Pythonでは、<a href="https://docs.python.org/3/reference/datamodel.html#context-managers" class="external-link" target="_blank">以下の２つのメソッドを持つクラスを作成する: `__enter__()`と`__exit__()`</a>ことでコンテキストマネージャを作成することができます。

また、依存関数の中で`with`や`async with`文を使用することによって`yield`を持つ **FastAPI** の依存関係の中でそれらを使用することができます:

```Python hl_lines="1 2 3 4 5 6 7 8 9 13"
{!../../docs_src/dependencies/tutorial010.py!}

///

В Python для создания менеджеров контекста можно <a href="https://docs.python.org/3/reference/datamodel.html#context-managers" class="external-link" target="_blank">создать класс с двумя методами: `__enter__()` и `__exit__()`</a>.

Вы также можете использовать их внутри зависимостей **FastAPI** с `yield`, используя операторы
`with` или `async with` внутри функции зависимости:

```Python hl_lines="1-9  13"

///

Em python, você pode criar Gerenciadores de Contexto ao <a href="https://docs.python.org/3/reference/datamodel.html#context-managers" class="external-link" target="_blank"> criar uma classe com dois métodos: `__enter__()` e `__exit__()`</a>.

Você também pode usá-los dentro de dependências com `yield` do **FastAPI** ao utilizar `with` ou `async with` dentro da função da dependência:

```Python hl_lines="1-9  13"

sub-modules, as described below.

Note that the file `__init__.py` in the TensorFlow source code tree is actually
only a placeholder to enable test cases to run. The TensorFlow build replaces
this file with a file generated from [`api_template.__init__.py`](https://www.github.com/tensorflow/tensorflow/blob/master/tensorflow/api_template.__init__.py)
"""
# pylint: disable=g-bad-import-order,protected-access,g-import-not-at-top