Hello Wade Wilson from Python
```

</div>

As environment variables can be set outside of the code, but can be read by the code, and don't have to be stored (committed to `git`) with the rest of the files, it's common to use them for configurations or settings.

You can also create an environment variable only for a specific program invocation, that is only available to that program, and only for its duration.

然后，`admin_email` 设置将为 `"******@****.***"`。

`app_name` 将为 `"ChimichangApp"`。

而 `items_per_user` 将保持其默认值为 `50`。

## 在另一个模块中设置

您可以将这些设置放在另一个模块文件中，就像您在[Bigger Applications - Multiple Files](../tutorial/bigger-applications.md){.internal-link target=_blank}中所见的那样。

例如，您可以创建一个名为 `config.py` 的文件，其中包含以下内容：

```Python
{!../../../docs_src/settings/app01/config.py!}
```

然后在一个名为 `main.py` 的文件中使用它：