## External Courses

Although the [Tutorial - User Guide](../tutorial/index.md){.internal-link target=_blank} and this **Advanced User Guide** are written as a guided tutorial (like a book) and should be enough for you to **learn FastAPI**, you might want to complement it with additional courses.

Or it might be the case that you just prefer to take other courses because they adapt better to your learning style.

    A `Response` returned directly by your *path operation function* won't be documented in OpenAPI (for example, the `Content-Type` won't be documented) and won't be visible in the automatic interactive docs.

!!! info
    Of course, the actual `Content-Type` header, status code, etc, will come from the `Response` object you returned.

### Document in OpenAPI and override `Response`

```Python hl_lines="8-15"
{!../../../docs_src/custom_request_and_route/tutorial001.py!}
```

### Eine benutzerdefinierte `GzipRoute`-Klasse erstellen

Als Nächstes erstellen wir eine benutzerdefinierte Unterklasse von `fastapi.routing.APIRoute`, welche `GzipRequest` nutzt.

Dieses Mal wird die Methode `APIRoute.get_route_handler()` überschrieben.

Or you might have any other way to communicate with the WebSocket endpoint.

---

But for this example, we'll use a very simple HTML document with some JavaScript, all inside a long string.

This, of course, is not optimal and you wouldn't use it for production.

In production you would have one of the options above.

But it's the simplest way to focus on the server-side of WebSockets and have a working example:

    hashed_password = hashed_password,
)
```

!!! warning
    The supporting additional functions are just to demo a possible flow of the data, but they of course are not providing any real security.

## Reduce duplication

Reducing code duplication is one of the core ideas in **FastAPI**.

      exercising permissions granted by this License.

      "Source" form shall mean the preferred form for making modifications,
      including but not limited to software source code, documentation
      source, and configuration files.

      "Object" form shall mean any form resulting from mechanical
      transformation or translation of a Source form, including but

Plus jamais vous ne vous tromperez en tapant le nom d'une clé, vous ne ferez des aller-retour entre votre code et la documentation ou vous ne scrollerez de haut en bas afin d'enfin savoir si vous devez taper `username` ou `user_name`.

### Court

Des **valeurs par défaut** sont définies pour tout, des configurations optionnelles sont présentent partout. Tous ces paramètres peuvent être ajustés afin de faire ce que vous voulez et définir l'API dont vous avez besoin.

import org.jetbrains.kotlin.resolve.sam.SamConstructorDescriptor
import org.jetbrains.kotlin.resolve.scopes.receivers.ImplicitContextReceiver
import org.jetbrains.kotlin.resolve.source.PsiSourceElement
import org.jetbrains.kotlin.resolve.source.getPsi
import org.jetbrains.kotlin.synthetic.SyntheticJavaPropertyDescriptor
import org.jetbrains.kotlin.types.*
import org.jetbrains.kotlin.types.checker.NewCapturedType

    ```

But know that this is deprecated and it should be updated to use the new parameter `pattern`. 🤓

## Default values

You can, of course, use default values other than `None`.

Let's say that you want to declare the `q` query parameter to have a `min_length` of `3`, and to have a default value of `"fixedquery"`:

=== "Python 3.9+"

  optional int32 replicas = 1;

  // selector is a label query over pods that should match the replicas count. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/
  // +optional
  // +mapType=atomic
  map<string, string> selector = 2;

  // label selector for pods that should match the replicas count. This is a serializated
  // version of both map-based and more expressive set-based selectors. This is done to