```Python hl_lines="3"
{!../../../docs_src/app_testing/test_main.py!}
```

...and have the code for the tests just like before.

## Testing: extended example

Now let's extend this example and add more details to see how to test different parts.

### Extended **FastAPI** app file

Let's continue with the same file structure as before:

```
.
├── app
│   ├── __init__.py

```Python
{**note.dict()}
```

`**note.dict()` "unpacks" the key value pairs directly, so, `{**note.dict()}` would be, more or less, a copy of `note.dict()`.

And then, we extend that copy `dict`, adding another key-value pair: `"id": last_record_id`:

```Python
{**note.dict(), "id": last_record_id}
```

So, the final result returned would be something like:

```Python
{

Any variable that is put inside of `{}` in an f-string will be expanded / injected in the string.

### `dict` unpacking

### Docs

* 📝 Update GraphQL docs, recommend Strawberry. PR [#3981](https://github.com/tiangolo/fastapi/pull/3981) by [@tiangolo](https://github.com/tiangolo).
* 📝 Re-write and extend Deployment guide: Concepts, Uvicorn, Gunicorn, Docker, Containers, Kubernetes. PR [#3974](https://github.com/tiangolo/fastapi/pull/3974) by [@tiangolo](https://github.com/tiangolo).

    * You can have deeply **nested JSON** objects and have them all validated and annotated.
* **Extensible**:
    * Pydantic allows custom data types to be defined or you can extend validation with methods on a model decorated with the validator decorator.

!!! tip
    This is a low level extension point.

    If you only need to declare additional responses, a more convenient way to do it is with [Additional Responses in OpenAPI](additional-responses.md){.internal-link target=_blank}.

You can extend the OpenAPI schema for a *path operation* using the parameter `openapi_extra`.

    You can set `schema_extra` with a `dict` containing any additional data you would like to show up in the generated JSON Schema, including `examples`.

!!! tip
    You could use the same technique to extend the JSON Schema and add your own custom extra info.

    For example you could use it to add metadata for a frontend user interface, etc.

!!! info

But you should first read the **Tutorial - User Guide** (what you are reading right now).