</h1>
                    </div>
                    <div class="col-sm-6">
                        <ol class="breadcrumb float-sm-right">
                            <li class="breadcrumb-item"><la:link href="/admin/wizard/">
                                <la:message key="labels.wizard_start_title"/>
                            </la:link></li>

# Modelos de Formulario { #form-models }

Puedes usar **modelos de Pydantic** para declarar **campos de formulario** en FastAPI.

/// info | Información

Para usar formularios, primero instala <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Asegúrate de crear un [entorno virtual](../virtual-environments.md){.internal-link target=_blank}, activarlo, y luego instalarlo, por ejemplo:

```console

package gradlebuild.binarycompatibility.rules

import japicmp.model.JApiClass
import japicmp.model.JApiCompatibility
import javassist.CtClass
import me.champeau.gradle.japicmp.report.Violation

/**
 * Workaround for <a href="https://github.com/melix/japicmp-gradle-plugin/issues/56">japicmp issue w.r.t. superclass breakage</a>.
 *
 * <p>

### Revisa la documentación { #check-the-docs }

Ahora puedes iniciar tu app e ir a <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

Verás que tu documentación tiene las *path operations* normales y ahora también algunos **webhooks**:

### Check the docs { #check-the-docs }

Now you can start your app and go to <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

You will see your docs have the normal *path operations* and now also some **webhooks**:

Now, let's see how you could use that to return a custom response.

Let's say that you want to return an <a href="https://en.wikipedia.org/wiki/XML" class="external-link" target="_blank">XML</a> response.

You could put your XML content in a string, put that in a `Response`, and return it:

По указанным причинам текущие версии до сих пор `0.x.x`. Это говорит о том, что каждая версия может содержать обратно несовместимые изменения, следуя <a href="https://semver.org/" class="external-link" target="_blank">Семантическому версионированию</a>.

Dies wird in OpenAPI mit `anyOf` definiert.

Um das zu tun, verwenden Sie den Standard-Python-Typhinweis <a href="https://docs.python.org/3/library/typing.html#typing.Union" class="external-link" target="_blank">`typing.Union`</a>:

/// note | Hinweis

Он будет определён в OpenAPI как `anyOf`.

Для этого используйте стандартную аннотацию типов в Python <a href="https://docs.python.org/3/library/typing.html#typing.Union" class="external-link" target="_blank">`typing.Union`</a>:

/// note | Примечание

## Official Guide { #official-guide }

Pydantic has an official <a href="https://docs.pydantic.dev/latest/migration/" class="external-link" target="_blank">Migration Guide</a> from v1 to v2.

It also includes what has changed, how validations are now more correct and strict, possible caveats, etc.