Você pode utilizar **Modelos Pydantic** para declarar **campos de formulários** no FastAPI.

/// info | Informação

Para utilizar formulários, instale primeiramente o <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Certifique-se de criar um [ambiente virtual](../virtual-environments.md){.internal-link target=_blank}, ativá-lo, e então instalar. Por exemplo:

```console

import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertTrue;

@Deprecated
class DefaultArtifactResolverTest extends AbstractArtifactComponentTestCase {
    @Inject
    private ArtifactResolver artifactResolver;

    private Artifact projectArtifact;

    @BeforeEach
    @Override

package gradlebuild.nullaway

import org.gradle.api.services.BuildService
import org.gradle.api.services.BuildServiceParameters
import java.io.Closeable
import java.util.concurrent.ConcurrentHashMap

internal abstract class NullawayStatusService : BuildService<BuildServiceParameters.None>, Closeable {
    private val projectsWithNullAwayEnabled = ConcurrentHashMap.newKeySet<String>()

### Входная модель в документации { #input-model-in-docs }

В документации это видно: у поля `description` нет **красной звёздочки** — оно не отмечено как обязательное:

<div class="screenshot">
<img src="/img/tutorial/separate-openapi-schemas/image01.png">
</div>

### Модель для выхода { #model-for-output }

Но если использовать ту же модель как выходную, как здесь:

# Geschichte, Design und Zukunft { #history-design-and-future }

Vor einiger Zeit fragte <a href="https://github.com/fastapi/fastapi/issues/3#issuecomment-454956920" class="external-link" target="_blank">ein **FastAPI**-Benutzer</a>:

> Was ist die Geschichte dieses Projekts? Es scheint aus dem Nichts in ein paar Wochen zu etwas Großartigem geworden zu sein [...]

Hier ist ein wenig über diese Geschichte.

## Alternativen { #alternatives }

但 FastAPI 还可以使用数据类（<a href="https://docs.python.org/3/library/dataclasses.html" class="external-link" target="_blank">`dataclasses`</a>）：

{* ../../docs_src/dataclasses_/tutorial001.py hl[1,7:12,19:20] *}

这还是借助于 **Pydantic** 及其<a href="https://pydantic-docs.helpmanual.io/usage/dataclasses/#use-of-stdlib-dataclasses-with-basemodel" class="external-link" target="_blank">内置的 `dataclasses`</a>。

        merger.merge(null, pt, null);
    }

    @Test
    void testMergeJdk() throws Exception {
        try (InputStream isDominant = MavenToolchainMergerTest.class.getResourceAsStream("toolchains-jdks.xml");
                InputStream isRecessive = MavenToolchainMergerTest.class.getResourceAsStream("toolchains-jdks.xml")) {
            PersistedToolchains dominant = read(isDominant);
            PersistedToolchains recessive = read(isRecessive);

from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None
    tags: set[str] = set()


@app.post(
    "/items/",
    response_model=Item,
    summary="Create an item",
    response_description="The created item",
)

			Parity: 6,
		},
	}

	// Object for test case 5 - RRS StorageClass defined as Parity 2, MetaData in PutObject requesting RRS Class
	// Reset global storage class flags
	object5 := "object5"
	metadata5 := make(map[string]string)
	metadata5["x-amz-storage-class"] = storageclass.RRS
	globalStorageClass.Update(storageclass.Config{
		RRS: storageclass.StorageClass{
			Parity: 2,
		},
	})

/// tip | Tipp

Der eigentliche Callback ist nur ein HTTP-Request.

Wenn Sie den Callback selbst implementieren, können Sie beispielsweise <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a> oder <a href="https://requests.readthedocs.io/" class="external-link" target="_blank">Requests</a> verwenden.

///

## Schreiben des Codes, der den Callback dokumentiert { #write-the-callback-documentation-code }