Declare o corpo utilizando tipos padrão Python, graças ao Pydantic.

```Python hl_lines="4  9-12  25-27"
from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool] = None


@app.get("/")
def read_root():

Declara el body usando las declaraciones de tipo estándares de Python gracias a Pydantic.

```Python hl_lines="2  7-10  23-25"
from fastapi import FastAPI
from pydantic import BaseModel
from typing import Union

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


@app.get("/")
def read_root():

from typing import List, Union

import pytest
from fastapi import FastAPI
from fastapi.exceptions import FastAPIError, ResponseValidationError
from fastapi.responses import JSONResponse, Response
from fastapi.testclient import TestClient
from pydantic import BaseModel


class BaseUser(BaseModel):
    name: str


class User(BaseUser):
    surname: str


class DBUser(User):
    password_hash: str

package org.codelibs.fess.suggest.converter;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.codelibs.fess.suggest.settings.AnalyzerSettings;
import org.codelibs.fess.suggest.settings.SuggestSettings;
import org.opensearch.action.admin.indices.analyze.AnalyzeAction;
import org.opensearch.action.admin.indices.analyze.AnalyzeAction.AnalyzeToken;
import org.opensearch.client.Client;

package org.codelibs.fess.suggest.settings;

import static org.codelibs.opensearch.runner.OpenSearchRunner.newConfigs;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotSame;

import org.codelibs.fess.suggest.Suggester;
import org.codelibs.opensearch.runner.OpenSearchRunner;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;

 */
package okhttp3.internal.connection

import java.io.IOException
import java.net.HttpURLConnection
import java.net.Socket
import java.net.UnknownServiceException
import okhttp3.Address
import okhttp3.ConnectionSpec
import okhttp3.HttpUrl
import okhttp3.Protocol
import okhttp3.Request
import okhttp3.Response
import okhttp3.Route
import okhttp3.internal.USER_AGENT
import okhttp3.internal.canReuseConnectionFor

 */

package com.google.common.util.concurrent;

import static com.google.common.base.StandardSystemProperty.JAVA_CLASS_PATH;
import static com.google.common.base.StandardSystemProperty.PATH_SEPARATOR;

import com.google.common.base.Splitter;
import com.google.common.collect.ImmutableList;
import java.io.File;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;

 */

package com.google.common.base;

import static com.google.common.base.NullnessCasts.uncheckedCastNullableTToT;
import static com.google.common.base.Preconditions.checkState;

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.Iterator;
import java.util.NoSuchElementException;
import javax.annotation.CheckForNull;

package org.apache.maven.artifact.resolver;

import java.io.File;
import java.io.InputStream;

import org.apache.maven.wagon.ResourceDoesNotExistException;
import org.apache.maven.wagon.TransferFailedException;
import org.apache.maven.wagon.authorization.AuthorizationException;
import org.apache.maven.wagon.events.TransferListener;
import org.apache.maven.wagon.providers.file.FileWagon;
import org.apache.maven.wagon.resource.Resource;

/**

 */
package org.apache.maven.project.inheritance.t12;

import java.io.File;
import java.util.Map;

import org.apache.maven.model.Plugin;
import org.apache.maven.project.MavenProject;
import org.apache.maven.project.inheritance.AbstractProjectInheritanceTestCase;
import org.junit.jupiter.api.Test;

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

/**