```Python hl_lines="1  7-13  19"
{!../../../docs_src/dataclasses/tutorial002.py!}
```

The dataclass will be automatically converted to a Pydantic dataclass.

This way, its schema will show up in the API docs user interface:

<img src="/img/tutorial/dataclasses/image01.png">

## Dataclasses in Nested Data Structures

{!../../../docs_src/templates/templates/item.html!}
```

### Template Context Values

In the HTML that contains:

{% raw %}

```jinja
Item ID: {{ id }}
```

{% endraw %}

...it will show the `id` taken from the "context" `dict` you passed:

```Python
{"id": id}
```

For example, with an ID of `42`, this would render:

```html
Item ID: 42
```

### Template `url_for` Arguments

It won't show up in the documentation, but other tools (such as Sphinx) will be able to use the rest.

```Python hl_lines="19-29"
{!../../../docs_src/path_operation_advanced_configuration/tutorial004.py!}
```

## Additional Responses

You probably have seen how to declare the `response_model` and `status_code` for a *path operation*.

      .isEqualTo("<< 0x00000003 10000 DATA          COMPRESSED")
  }

  /**
   * Ensures that valid flag combinations appear visually correct, and invalid show in hex.  This
   * also demonstrates how sparse the lookup table is.
   */
  @Test
  fun allFormattedFlagsWithValidBits() {
    val formattedFlags = mutableListOf<String>() // Highest valid flag is 0x20.

## Lifespan

You can define this *startup* and *shutdown* logic using the `lifespan` parameter of the `FastAPI` app, and a "context manager" (I'll show you what that is in a second).

Let's start with an example and then see it in detail.

We create an async function `lifespan()` with `yield` like this:

```Python hl_lines="16  19"

    url: https://github.com/tiangolo/fastapi/discussions/categories/questions
  - name: Show and tell
    about: Show what you built with FastAPI or to be used with FastAPI.
    url: https://github.com/tiangolo/fastapi/discussions/categories/show-and-tell
  - name: Translations
    about: Coordinate translations in GitHub Discussions.

font-weight: bold;
L286:  padding: 4px 8px;
L287:}
L288:
L289:.daterangepicker.show-ranges.single.rtl .drp-calendar.left {
L290:  border-right: 1px solid #ddd;
L291:}
L292:
L293:.daterangepicker.show-ranges.single.ltr .drp-calendar.left {
L294:  border-left: 1px solid #ddd;
L295:}
L296:
L297:.daterangepicker.show-ranges.rtl .drp-calendar.right {
L298:  border-right: 1px solid #ddd;
L299:}
L300:
L301:.daterangepicker.show-ranges.ltr .drp-calendar.left {
L302:  border-left: 1px solid #ddd;
L303:}
...

Another more targeted interface is `CompilationFailedIndicator`.
This interface is used to indicate that the exception is caused by a compilation failure. 

### Download and Install/Run

Fess 14.12 is now available and can be downloaded on the [Releases page](https://github.com/codelibs/fess/releases "download"). Downloads come in 3 flavors: deb, rpm, zip.

The following commands show how to use the zip download:

    $ unzip fess-14.12.x.zip
    $ cd fess-14.12.x
    $ ./bin/fess

For more details, see the [Installation Guide](https://fess.codelibs.org/14.12/install/index.html).

### Docker

# Exceptions - `HTTPException` and `WebSocketException`

These are the exceptions that you can raise to show errors to the client.

When you raise an exception, as would happen with normal Python, the rest of the execution is aborted. This way you can raise these exceptions from anywhere in the code to abort a request and show the error to the client.

You can use:

* `HTTPException`
* `WebSocketException`