Pode ser útil para retornar cabeçalhos e cookies personalizados, por exemplo.

## Retornando uma `Response` { #return-a-response }

Na verdade, você pode retornar qualquer `Response` ou subclasse dela.

/// tip | Dica

A própria `JSONResponse` é uma subclasse de `Response`.

///

E quando você retorna uma `Response`, o **FastAPI** vai repassá-la diretamente.

/**
 * A {@link ListenableFuture} which forwards all its method calls to another future. Subclasses
 * should override one or more methods to modify the behavior of the backing future as desired per
 * the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p>Most subclasses can just use {@link SimpleForwardingListenableFuture}.
 *
 * @author Shardul Deo
 * @since 4.0
 */

/**
 * A {@link ListenableFuture} which forwards all its method calls to another future. Subclasses
 * should override one or more methods to modify the behavior of the backing future as desired per
 * the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p>Most subclasses can just use {@link SimpleForwardingListenableFuture}.
 *
 * @author Shardul Deo
 * @since 4.0
 */

    }

    /**
     * Sets the job class to be executed by this scheduler.
     *
     * @param jobClass the job class to set
     */
    public void setJobClass(final Class<? extends LaJob> jobClass) {
        this.jobClass = jobClass;
    }

avoids/fixes a potential security issue: as the returned object is passed directly to Pydantic, if the returned object was a subclass of the `response_model` (e.g. you return a `UserInDB` that inherits from `User` but contains extra fields, like `hashed_password`, and `User` is used in the `response_model`), it would still pass the validation (because `UserInDB` is a subclass of `User`) and the object would be returned as-is, including the `hashed_password`. To fix this, the declared `response_model`...

## Devolver una `Response` { #return-a-response }

De hecho, puedes devolver cualquier `Response` o cualquier subclase de ella.

/// tip | Consejo

`JSONResponse` en sí misma es una subclase de `Response`.

///

Y cuando devuelves una `Response`, **FastAPI** la pasará directamente.

import java.util.concurrent.Callable;
import org.jspecify.annotations.Nullable;

/**
 * A listening executor service which forwards all its method calls to another listening executor
 * service. Subclasses should override one or more methods to modify the behavior of the backing
 * executor service as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.List;
import org.jspecify.annotations.Nullable;

/**
 * A list multimap which forwards all its method calls to another list multimap. Subclasses should
 * override one or more methods to modify the behavior of the backing multimap as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *

        _ * classDoc.classProperties >> []
        _ * classDoc.classMethods >> []
        _ * classDoc.classBlocks >> []
        _ * classDoc.classExtensions >> []
        _ * classDoc.subClasses >> []

        when:
        def result = parse('<root/>')
        withCategories {
            renderer.mergeContent(classDoc, result)
        }

        then:
        formatTree(result) == '''<root>

 *
 * <p>In addition to {@link #execute}, subclasses must implement all methods related to shutdown and
 * termination.
 *
 * @author Chris Povirk
 * @since 14.0
 */
@CheckReturnValue
@GwtIncompatible
public abstract class AbstractListeningExecutorService extends AbstractExecutorService
    implements ListeningExecutorService {
  /** Constructor for use by subclasses. */
  public AbstractListeningExecutorService() {}