),
        ] = None,
        discriminator: Union[str, None] = None,
        strict: Union[bool, None] = _Unset,
        multiple_of: Union[float, None] = _Unset,
        allow_inf_nan: Union[bool, None] = _Unset,
        max_digits: Union[int, None] = _Unset,
        decimal_places: Union[int, None] = _Unset,
        examples: Optional[List[Any]] = None,
        example: Annotated[

        ),
    ] = None,
    discriminator: Annotated[
        Union[str, None],
        Doc(
            """
            Parameter field name for discriminating the type in a tagged union.
            """
        ),
    ] = None,
    strict: Annotated[
        Union[bool, None],
        Doc(
            """
            If `True`, strict validation is applied to the field.

    headers: Optional[Dict[str, Union[Header, Reference]]] = None
    securitySchemes: Optional[Dict[str, Union[SecurityScheme, Reference]]] = None
    links: Optional[Dict[str, Union[Link, Reference]]] = None
    # Using Any for Specification Extensions
    callbacks: Optional[Dict[str, Union[Dict[str, PathItem], Reference, Any]]] = None
    pathItems: Optional[Dict[str, Union[PathItem, Reference]]] = None

            main_dict[key] = main_dict[key] + update_dict[key]
        else:
            main_dict[key] = value


def get_value_or_default(
    first_item: Union[DefaultPlaceholder, DefaultType],
    *extra_items: Union[DefaultPlaceholder, DefaultType],
) -> Union[DefaultPlaceholder, DefaultType]:
    """
    Pass items or `DefaultPlaceholder`s by descending priority.

        function: Callable[..., Any],
        *,
        ref: Union[str, None] = None,
        metadata: Any = None,
        serialization: Any = None,
    ) -> Any:
        return {}

    def get_model_definitions(
        *,
        flat_models: Set[Union[Type[BaseModel], Type[Enum]]],
        model_name_map: Dict[Union[Type[BaseModel], Type[Enum]], str],
    ) -> Dict[str, Any]:

!!! note "Hinweis"

    {!> ../../../docs_src/extra_models/tutorial002_py310.py!}
    ```

## `Union` ⚖️ `anyOf`

👆 💪 📣 📨 `Union` 2️⃣ 🆎, 👈 ⛓, 👈 📨 🔜 🙆 2️⃣.

⚫️ 🔜 🔬 🗄 ⏮️ `anyOf`.

👈, ⚙️ 🐩 🐍 🆎 🔑 <a href="https://docs.python.org/3/library/typing.html#typing.Union" class="external-link" target="_blank">`typing.Union`</a>:

!!! note

#### <abbr title="Union – Verbund, Einheit‚ Vereinigung: Eines von Mehreren">Union</abbr>

Sie können deklarieren, dass eine Variable einer von **verschiedenen Typen** sein kann, zum Beispiel ein `int` oder ein `str`.

In Python 3.6 und höher (inklusive Python 3.10) können Sie den `Union`-Typ von `typing` verwenden und die möglichen Typen innerhalb der eckigen Klammern auflisten.

from datetime import datetime, time, timedelta
from typing import Union
from uuid import UUID

from fastapi import Body, FastAPI

app = FastAPI()


@app.put("/items/{item_id}")
async def read_items(
    item_id: UUID,
    start_datetime: datetime = Body(),
    end_datetime: datetime = Body(),
    process_after: timedelta = Body(),
    repeat_at: Union[time, None] = Body(default=None),
):

    ```

## `Union` or `anyOf`

You can declare a response to be the `Union` of two types, that means, that the response would be any of the two.

It will be defined in OpenAPI with `anyOf`.

To do that, use the standard Python type hint <a href="https://docs.python.org/3/library/typing.html#typing.Union" class="external-link" target="_blank">`typing.Union`</a>:

!!! note