## Usando `BackgroundTasks` { #using-backgroundtasks }

Primero, importa `BackgroundTasks` y define un parámetro en tu *path operation function* con una declaración de tipo de `BackgroundTasks`:

{* ../../docs_src/background_tasks/tutorial001_py39.py hl[1,13] *}

**FastAPI** creará el objeto de tipo `BackgroundTasks` por ti y lo pasará como ese parámetro.

    end
    dep ->> operation: Executar dependência, e.g. sessão de BD
    opt raise
        operation -->> dep: Lançar exceção (e.g. HTTPException)
        opt handle
            dep -->> dep: Pode capturar exceções, lançar uma nova HTTPException, lançar outras exceções
        end
        handler -->> client: resposta de erro HTTP
    end

    operation ->> client: Retornar resposta ao cliente

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

package jcifs.smb1.dcerpc.msrpc;

import jcifs.smb1.dcerpc.rpc;

/**
 * MS-RPC SAMR close handle operation.
 *
 * This class implements the SAMR CloseHandle operation for releasing
 * Security Account Manager (SAM) handles.
 */
public class MsrpcSamrCloseHandle extends samr.SamrCloseHandle {

    /**
     * Creates a new request to close a SAM handle.

Ein „Pfad“ wird häufig auch als „Endpunkt“ oder „Route“ bezeichnet.

///

Bei der Erstellung einer API ist der „Pfad“ die wichtigste Möglichkeit zur Trennung von „Anliegen“ und „Ressourcen“.

#### Operation { #operation }

„Operation“ bezieht sich hier auf eine der HTTP-„Methoden“.

Eine von diesen:

* `POST`
* `GET`
* `PUT`
* `DELETE`

... und die etwas Exotischeren:

* `OPTIONS`
* `HEAD`

Logo, a seção com:

{% raw %}

```jinja
<a href="{{ url_for('read_item', id=id) }}">
```

{% endraw %}

...irá gerar um link para a mesma URL que será tratada pela *path operation function* `read_item(id=id)`.

Por exemplo, com um ID de `42`, isso renderizará:

```html

import java.util.List;

import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.services.Request;
import org.apache.maven.api.services.Result;

/**
 * Exception thrown when a batch request operation fails. This exception contains the results
 * of all requests that were attempted, including both successful and failed operations.
 * <p>
 * The exception provides access to detailed results through {@link #getResults()}, allowing

# Additional Status Codes { #additional-status-codes }

By default, **FastAPI** will return the responses using a `JSONResponse`, putting the content you return from your *path operation* inside of that `JSONResponse`.

It will use the default status code or the one you set in your *path operation*.

## Additional status codes { #additional-status-codes_1 }

     * @throws DcerpcException if the wrapping operation fails
     */
    void wrap(NdrBuffer outgoing) throws DcerpcException;

    /**
     * Unwraps incoming DCERPC message data after security processing
     * @param incoming the buffer containing data to be unwrapped
     * @throws DcerpcException if the unwrapping operation fails
     */
    void unwrap(NdrBuffer incoming) throws DcerpcException;

 */

package jcifs.dcerpc.msrpc;

import jcifs.dcerpc.ndr.NdrObject;

/**
 * MS-RPC query information policy operation.
 *
 * This class implements the LSARPC QueryInformationPolicy operation
 * for retrieving policy information from the Local Security Authority (LSA).
 */
public class MsrpcQueryInformationPolicy extends lsarpc.LsarQueryInformationPolicy {

    /**

        dep -->> dep: Raise other exception
    end
    dep ->> operation: Run dependency, e.g. DB session
    opt raise
        operation -->> handler: Raise HTTPException
        handler -->> client: HTTP error response
        operation -->> dep: Raise other exception
    end
    operation ->> client: Return response to client
    Note over client,operation: Response is already sent, can't change it anymore
    opt Tasks