@app.get("/items/{item_id}")
async def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

**Note**

Si vous n'êtes pas familier avec cette notion, consultez la section _"Vous êtes pressés ?"_ à propos de <a href="https://fastapi.tiangolo.com/fr/async/#vous-etes-presses" target="_blank">`async` et `await` dans la documentation</a>.

</details>

| Params     | Value    |
| :--        | :--      |
| *Type*     | *String* |
| *Required* | *Yes*    |

### AUTHPARAMS

Indicates STS API Authorization information. If you are familiar with AWS Signature V4 Authorization header, this STS API supports signature V4 authorization as mentioned [here](https://docs.aws.amazon.com/general/latest/gr/signature-version-4.html)

### DurationSeconds

It is based on <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a>, which in turn is designed based on Requests, so it's very familiar and intuitive.

With it, you can use <a href="https://docs.pytest.org/" class="external-link" target="_blank">pytest</a> directly with **FastAPI**.

## Using `TestClient` { #using-testclient }

/// info

It will have a *path operation* that will receive an `Invoice` body, and a query parameter `callback_url` that will contain the URL for the callback.

This part is pretty normal, most of the code is probably already familiar to you:

{* ../../docs_src/openapi_callbacks/tutorial001.py hl[9:13,36:53] *}

/// tip

* Técnicas más avanzadas (pero igualmente fáciles) para declarar **modelos JSON profundamente anidados** (gracias a Pydantic).
* Integración con **GraphQL** usando <a href="https://strawberry.rocks" class="external-link" target="_blank">Strawberry</a> y otros paquetes.
* Muchas funcionalidades extra (gracias a Starlette) como:
    * **WebSockets**
    * pruebas extremadamente fáciles basadas en HTTPX y `pytest`
    * **CORS**

labels.user_given_name=Prénom
labels.givenName=Prénom (nom donné)
labels.user_surname=Nom de famille
labels.surame=Nom de famille
labels.user_mail=E-mail
labels.mail=E-mail
labels.user_employeeNumber=Numéro d'employé
labels.employeeNumber=Numéro d'employé
labels.user_telephoneNumber=Numéro de téléphone

   *
   * <p><b>Warning:</b> in most circumstances it is better to set a per-cache {@linkplain
   * #maximumSize(long) maximum size} instead of using soft references. You should only use this
   * method if you are well familiar with the practical consequences of soft references.
   *
   * <p><b>Note:</b> when this method is used, the resulting cache will use identity ({@code ==})
   * comparison to determine equality of values.
   *

express
express.aero
express.val.run
extraspace
ezproxy.kuleuven.be
f.bg
f.se
f5.si
fage
fail
fairwinds
faith
fakefur.jp
fam.pk
family
familyds.com
familyds.net
familyds.org
fan
fans
fantasyleague.cc
far.br
farm
farmers
farsund.no
fashion
fashionstore.jp
fast
fastly-edge.com
fastly-terrarium.com
fastlylb.net