{!../../../docs_src/python_types/tutorial009.py!}
```

Utiliser `Optional[str]` plutôt que `str` permettra à l'éditeur de vous aider à détecter les erreurs où vous supposeriez qu'une valeur est toujours de type `str`, alors qu'elle pourrait aussi être `None`.

#### Types génériques

Les types qui peuvent contenir des paramètres de types entre crochets, comme :

* `List`
* `Tuple`
* `Set`
* `Dict`
* `Optional`

  // +optional
  repeated string hosts = 1;

  // secretName is the name of the secret used to terminate TLS traffic on
  // port 443. Field is left optional to allow TLS routing based on SNI
  // hostname alone. If the SNI host in a listener conflicts with the "Host"
  // header field used by an IngressRule, the SNI host is used for termination
  // and value of the Host header is used for routing.
  // +optional

## Reference

### Design details

section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer the Work, where such license applies only to those patent claims licensable by such Contributor that are necessarily infringed by their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted. If You institute patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that the Work or a Contribution...

contributions, often because we probably won't get to them right now. If you
decide to start on an issue, leave a comment so that other people know that
you're working on it. If you want to help out, but not alone, use the issue
comment thread to coordinate.

### Contribution guidelines and standards

Before sending your pull request for
[review](https://github.com/tensorflow/tensorflow/pulls),

Por ejemplo:

* **Audio** o **procesamiento de imágenes**.
* **Visión por computadora**: una imagen está compuesta de millones de píxeles, cada píxel tiene 3 valores / colores, procesamiento que normalmente requiere calcular algo en esos píxeles, todo al mismo tiempo.

!!! check "**FastAPI** inspirado para"
    Definir validações extras para tipos de dados usando valores "padrão" de atributos dos modelos. Isso melhora o suporte do editor, e não estava disponível no Pydantic antes.

  // +optional
  repeated string hosts = 1;

  // secretName is the name of the secret used to terminate TLS traffic on
  // port 443. Field is left optional to allow TLS routing based on SNI
  // hostname alone. If the SNI host in a listener conflicts with the "Host"
  // header field used by an IngressRule, the SNI host is used for termination
  // and value of the "Host" header is used for routing.
  // +optional

      use, offer to sell, sell, import, and otherwise transfer the Work,
      where such license applies only to those patent claims licensable
      by such Contributor that are necessarily infringed by their
      Contribution(s) alone or by combination of their Contribution(s)
      with the Work to which such Contribution(s) was submitted. If You
      institute patent litigation against any entity (including a

* Tecniche più avanzate (ma ugualmente semplici) per dichiarare **modelli JSON altamente nidificati** (grazie a Pydantic).
* E altre funzionalità (grazie a Starlette) come:
    * **WebSockets**
    * **GraphQL**
    * test molto facili basati su `requests` e `pytest`
    * **CORS**
    * **Cookie Sessions**
    * ...e altro ancora.