Then, you try with the old programmer's friend, editor autocompletion.

You type the first parameter of the function, `first_name`, then a dot (`.`) and then hit `Ctrl+Space` to trigger the completion.

But, sadly, you get nothing useful:

<img src="/img/python-types/image01.png">

### Add types

Let's modify a single line from the previous version.

* 🐛 Prefer custom encoder over defaults if specified in `jsonable_encoder`. PR [#2061](https://github.com/tiangolo/fastapi/pull/2061) by [@viveksunder](https://github.com/viveksunder).
    * 💚 Duplicate PR to trigger CI. PR [#4467](https://github.com/tiangolo/fastapi/pull/4467) by [@tiangolo](https://github.com/tiangolo).

### Internal

# OpenAPI Callbacks

You could create an API with a *path operation* that could trigger a request to an *external API* created by someone else (probably the same developer that would be *using* your API).

!!! tip
    Note that we're using async/await with the new `AsyncClient` - the request is asynchronous.

!!! warning
    If your application relies on lifespan events, the `AsyncClient` won't trigger these events. To ensure they are triggered, use `LifespanManager` from <a href="https://github.com/florimondmanca/asgi-lifespan#usage" class="external-link" target="_blank">florimondmanca/asgi-lifespan</a>.

And as your app starts to handle more and more clients at the same time, the waiting time in a single request needs to be shorter and shorter to trigger the error.

### Fix Peewee with FastAPI

Now go back to the file `sql_app/database.py`, and uncomment the line:

```Python
db._state = PeeweeConnectionState()
```