// configuration, the controller will stop creating new new Jobs and will create a system event with the
  // reason UnknownTimeZone.
  // More information can be found in https://kubernetes.io/docs/concepts/workloads/controllers/cron-jobs/#time-zones
  // +optional
  optional string timeZone = 8;

  // Optional deadline in seconds for starting the job if it misses scheduled

由于与 SQLAlchemy 和 SQLAlchemy 模型相关的代码位于单独的独立文件中，您甚至可以使用 Alembic 执行迁移，而无需安装 FastAPI、Pydantic 或其他任何东西。

同样，您将能够在与**FastAPI**无关的代码的其他部分中使用相同的 SQLAlchemy 模型和实用程序。

例如，在具有[Celery](https://docs.celeryq.dev/)、[RQ](https://python-rq.org/)或[ARQ](https://arq-docs.helpmanual.io/)的后台任务工作者中。

## 审查所有文件

最后回顾整个案例，您应该有一个名为的目录`my_super_project`，其中包含一个名为`sql_app`。

`sql_app`中应该有以下文件：

* `sql_app/__init__.py`：这是一个空文件。

 [advanced_profiling_bug]: https://issuetracker.google.com/issues/135141615
 [japicmp]: https://github.com/siom79/japicmp
 [japicmp_gradle]: https://github.com/melix/japicmp-gradle-plugin
 [java_sams]: https://kotlinlang.org/docs/reference/java-interop.html#sam-conversions
 [kotlin_sams]: https://youtrack.jetbrains.com/issue/KT-11129
 [mockito]: https://site.mockito.org/
 [proguard_problems]: https://github.com/square/okhttp/issues/5167

```Python hl_lines="3"
import os

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

/// tip

Het tweede argument van <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> is de standaardwaarde die wordt geretourneerd.

```Python hl_lines="3"
import os

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

/// tip

The second argument to <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> is the default value to return.

If not provided, it's `None` by default, here we provide `"World"` as the default value to use.

Abgesehen von normalen einfachen Typen, wie `str`, `int`, `float`, usw. können Sie komplexere einfache Typen verwenden, die von `str` erben.

Um alle Optionen kennenzulernen, die Sie haben, schauen Sie sich <a href="https://docs.pydantic.dev/latest/concepts/types/" class="external-link" target="_blank">Pydantics Typübersicht</a> an. Sie werden im nächsten Kapitel ein paar Beispiele kennenlernen.

/// info

You can read more about the Starlette `lifespan` handlers in <a href="https://www.starlette.io/lifespan/" class="external-link" target="_blank">Starlette's  Lifespan' docs</a>.

Including how to handle lifespan state that can be used in other areas of your code.

///

## Sub Applications

```Python hl_lines="6"
{!../../docs_src/python_types/tutorial010.py!}
```

그리고 역시나 모든 에디터 도움을 받게 되겠죠.

<img src="/img/python-types/image06.png">

## Pydantic 모델

<a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a>은 데이터 검증(Validation)을 위한 파이썬 라이브러리입니다.

당신은 속성들을 포함한 클래스 형태로 "모양(shape)"을 선언할 수 있습니다.

그리고 각 속성은 타입을 가지고 있습니다.

				return err
			}

			if len(outputMsgs) == 0 {
				message := " No issues found when checking the cluster. Istio is safe to install or upgrade!"
				message += "\n  To get started, check out https://istio.io/latest/docs/setup/getting-started/."
				_, _ = fmt.Fprintln(cmd.ErrOrStderr(), color.New(color.FgGreen).Sprint("✔")+message)
			} else {
				_, _ = fmt.Fprintln(cmd.OutOrStdout(), output)
			}
			for _, m := range msgs {

# Controllers

Istio has a variety of [controllers](https://kubernetes.io/docs/concepts/architecture/controller/), which basically watch some inputs and do something.
This can be reading from Kubernetes and writing other objects back, writing to proxies over XDS, etc.

Unfortunately, writing controllers is very error prone, even for seemingly simple cases.
To work around this, Istio has a variety of abstractions meant to make writing controllers easier.

## Clients