`Optional[Something]` é na verdade um atalho para `Union[Something, None]`, eles são equivalentes.

Isso também significa que no Python 3.10, você pode utilizar `Something | None`:

//// tab | Python 3.10+

```Python hl_lines="1"
{!> ../../docs_src/python_types/tutorial009_py310.py!}
```

     */
    @InputFile
    @PathSensitive(PathSensitivity.NONE)
    public abstract RegularFileProperty getHtmlFile();

    /**
     * The decorated HTML file
     */
    @OutputFile
    public abstract RegularFileProperty getDestinationFile();

    /**
     * JQuery used by the added decoration
     */
    @InputFiles
    @PathSensitive(PathSensitivity.NONE)
    public abstract ConfigurableFileCollection getJquery();

        """
        if self.cid is not None:
            fetcher = self._create_credentials_fetcher()
            return RefreshableCredentials.create_from_metadata(
                metadata=fetcher(),
                refresh_using=fetcher,
                method=self.METHOD,
            )
        else:
            return None

    def _create_credentials_fetcher(self):
        method = self.METHOD

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


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


@app.put("/items/{item_id}")
def update_item(item_id: int, item: Item):

`Optional[Something]` is actually a shortcut for `Union[Something, None]`, they are equivalent.

This also means that in Python 3.10, you can use `Something | None`:

//// tab | Python 3.10+

```Python hl_lines="1"
{!> ../../docs_src/python_types/tutorial009_py310.py!}
```

    "bar": {"id": "bar", "title": "Bar", "description": "The bartenders"},
}

app = FastAPI()


class Item(BaseModel):
    id: str
    title: str
    description: Union[str, None] = None


@app.get("/items/{item_id}", response_model=Item)
async def read_main(item_id: str, x_token: str = Header()):
    if x_token != fake_secret_token:

		{xForwardedFor, "", ""},                                                       // None
		{xRealIP, "8.8.8.8", "8.8.8.8"},                                               // Single address
		{xRealIP, "[2001:db8:cafe::17]:4711", "[2001:db8:cafe::17]"},                  // IPv6 address
		{xRealIP, "", ""},                                                             // None
		{forwarded, `for="_gazonk"`, "_gazonk"},                                       // Hostname

                """
            ),
        ],
    ) -> None:
        """
        Move to a position in the file.

        Any next read or write will be done from that position.

        To be awaitable, compatible with async, this is run in threadpool.
        """
        return await super().seek(offset)

    async def close(self) -> None:
        """
        Close the file.

    "bar": {"id": "bar", "title": "Bar", "description": "The bartenders"},
}

app = FastAPI()


class Item(BaseModel):
    id: str
    title: str
    description: str | None = None


@app.get("/items/{item_id}", response_model=Item)
async def read_main(item_id: str, x_token: Annotated[str, Header()]):
    if x_token != fake_secret_token:

    rules:
      - apiGroups:
          - ""
        apiVersions:
          - v1
        operations:
          - CREATE
        resources:
          - pods
        scope: '*'
    sideEffects: None
    timeoutSeconds: 10
  - admissionReviewVersions:
      - v1beta1
      - v1
    clientConfig:
      service:
        name: istiod
        namespace: istio-system
        path: /inject
        port: 443