É apenas uma função padrão que pode receber parâmetros.

Pode ser uma função `async def` ou `def` normal, o **FastAPI** saberá como lidar com isso corretamente.

Nesse caso, a função de tarefa gravará em um arquivo (simulando o envio de um e-mail).

E como a operação de gravação não usa `async` e `await`, definimos a função com `def` normal:

```Python hl_lines="6-9"
{!../../docs_src/background_tasks/tutorial001.py!}
```

It is just a standard function that can receive parameters.

It can be an `async def` or normal `def` function, **FastAPI** will know how to handle it correctly.

In this case, the task function will write to a file (simulating sending an email).

And as the write operation doesn't use `async` and `await`, we define the function with normal `def`:

{* ../../docs_src/background_tasks/tutorial001.py hl[6:9] *}

## Add the background task

 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven;

import org.apache.maven.plugin.MojoFailureException;

/**
 * Exception which occurs when a normal (i.e. non-aggregator) mojo fails to
 * execute. In this case, the mojo failed while executing against a particular
 * project instance, so we can wrap the {@link MojoFailureException} with context

```Python hl_lines="2  12  15-18"
{!../../docs_src/app_testing/tutorial001.py!}
```

/// tip

Notice that the testing functions are normal `def`, not `async def`.

And the calls to the client are also normal calls, not using `await`.

This allows you to use `pytest` directly without complications.

///

/// note | "Technical Details"

* `datetime.date`:
    * Python `datetime.date`.
    * In requests and responses will be represented as a `str` in ISO 8601 format, like: `2008-09-15`.
* `datetime.time`:
    * A Python `datetime.time`.
    * In requests and responses will be represented as a `str` in ISO 8601 format, like: `14:23:55.003`.
* `datetime.timedelta`:

### Otras funciones de utilidades

Cualquier otra función de utilidad que llames directamente se puede crear con `def` o `async def` normales y FastAPI no afectará la manera en que la llames.

value="<font face="Roboto" data-font-src="https://fonts.googleapis.com/css?family=Roboto" style="font-size: 24px ; font-weight: normal">Another app</font><font face="Roboto" data-font-src="https://fonts.googleapis.com/css?family=Roboto" style="font-size: 24px ; font-weight: normal">: another.example.com</font>" style="rounded=0;whiteSpace=wrap;html=1;fontStyle=1;strokeWidth=4;fillColor=#dae8fc;strokeColor=#6c8ebf;" parent="1"...

		ACB_PWNOTREQ               = 0x00000004, /* 1 = User password not required */
		ACB_TEMPDUP                = 0x00000008, /* 1 = Temporary duplicate account */
		ACB_NORMAL                 = 0x00000010, /* 1 = Normal user account */
		ACB_MNS                    = 0x00000020, /* 1 = MNS logon user account */
		ACB_DOMTRUST               = 0x00000040, /* 1 = Interdomain trust account */

# GraphQL

As **FastAPI** is based on the **ASGI** standard, it's very easy to integrate any **GraphQL** library also compatible with ASGI.

You can combine normal FastAPI *path operations* with GraphQL on the same application.

/// tip

**GraphQL** solves some very specific use cases.

It has **advantages** and **disadvantages** when compared to common **web APIs**.

Isso significa que no lugar do processo normal de seus usuários enviarem requisições para a sua API, é a **sua API** (ou sua aplicação) que poderia **enviar requisições para o sistema deles** (para a API deles, a aplicação deles).

Isso normalmente é chamado de **webhook**.