Deze informatie is handig wanneer je meer wilt weten over [virtuele omgevingen](virtual-environments.md){.internal-link target=_blank}.

## Conclusion

Hiermee heb je basiskennis van wat **omgevingsvariabelen** zijn en hoe je ze in Python kunt gebruiken.

Je kunt er ook meer over lezen op de <a href="https://en.wikipedia.org/wiki/Environment_variable" class="external-link" target="_blank">Wikipedia over omgevingsvariabelen</a>.

{!../../docs_src/app_testing/tutorial002.py!}
```

/// note | "Nota"

Para mais detalhes, confira a documentação do Starlette para <a href="https://www.starlette.io/testclient/#testing-websocket-sessions" class="external-link" target="_blank">testar WebSockets</a>.

}

/**
 * Walk the resolved graph and discover all external dependencies that are not transitive dependencies
 * of project dependencies. This optimizes module loading during runtime, as we will only load external
 * modules that are not loaded transitively by other project modules.
 *
 * We perform this filtering, since if we simply include all external dependencies, regardless of whether

# Automatic Site Replication

This feature allows multiple independent MinIO sites (or clusters) that are using the same external IDentity Provider (IDP) to be configured as replicas. In this situation the set of replica sites are referred to as peer sites or just sites. When site-replication is enabled on a set of sites, the following changes are replicated to all other sites:

- Creation and deletion of buckets and objects

  // external refers to a global metric that is not associated
  // with any Kubernetes object. It allows autoscaling based on information
  // coming from components running outside of cluster
  // (for example length of queue in cloud messaging service, or
  // QPS from loadbalancer running outside of cluster).
  // +optional
  optional ExternalMetricSource external = 5;
}

Sie akzeptiert zum Beispiel keine `datetime`-Objekte, da die nicht kompatibel mit JSON sind.

Ein `datetime`-Objekt müsste also in einen `str` umgewandelt werden, der die Daten im <a href="https://en.wikipedia.org/wiki/ISO_8601" class="external-link" target="_blank">ISO-Format</a> enthält.

Genauso würde die Datenbank kein Pydantic-Modell (ein Objekt mit Attributen) akzeptieren, sondern nur ein `dict`.

Sie können für diese Fälle `jsonable_encoder` verwenden.

```Python hl_lines="3"
import os

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

/// tip

<a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> 的第二个参数是要返回的默认值。

如果没有提供默认值，默认为 `None`，此处我们提供了 `"World"` 作为要使用的默认值。

///

然后，您可以调用该 Python 程序：

<div class="termy">

```console
// 这里我们还没有设置环境变量

Когда вам нужно получить поля формы вместо JSON, вы можете использовать `Form`.

/// info | "Дополнительная информация"

Чтобы использовать формы, сначала установите <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Например, выполните команду `pip install python-multipart`.

///

## Импорт `Form`

Импортируйте `Form` из `fastapi`:

//// tab | Python 3.9+

/// info

`status_code` can alternatively also receive an `IntEnum`, such as Python's <a href="https://docs.python.org/3/library/http.html#http.HTTPStatus" class="external-link" target="_blank">`http.HTTPStatus`</a>.

///

It will:

* Return that status code in the response.
* Document it as such in the OpenAPI schema (and so, in the user interfaces):

{* ../../docs_src/dataclasses/tutorial001.py hl[1,7:12,19:20] *}

This is still supported thanks to **Pydantic**, as it has <a href="https://docs.pydantic.dev/latest/concepts/dataclasses/#use-of-stdlib-dataclasses-with-basemodel" class="external-link" target="_blank">internal support for `dataclasses`</a>.