En ese caso, simplemente puedes intercambiar los `dataclasses` estándar con `pydantic.dataclasses`, que es un reemplazo directo:

{* ../../docs_src/dataclasses_/tutorial003_py310.py hl[1,4,7:10,13:16,22:24,27] *}

1. Todavía importamos `field` de los `dataclasses` estándar.

2. `pydantic.dataclasses` es un reemplazo directo para `dataclasses`.

3. El dataclass `Author` incluye una lista de dataclasses `Item`.

Es wird von Pydantic **nicht unterstützt**, dass ein Pydantic‑v2‑Modell Felder hat, die als Pydantic‑v1‑Modelle definiert sind, und umgekehrt.

```mermaid
graph TB
    subgraph "❌ Nicht unterstützt"
        direction TB
        subgraph V2["Pydantic-v2-Modell"]
            V1Field["Pydantic-v1-Modell"]
        end
        subgraph V1["Pydantic-v1-Modell"]
            V2Field["Pydantic-v2-Modell"]
        end
    end

            Optional[int],
            Doc(
                """
                The default status code to be used for the response.

                You could override the status code by returning a response directly.

                Read more about it in the
                [FastAPI docs for Response Status Code](https://fastapi.tiangolo.com/tutorial/response-status-code/).
                """
            ),

        from ._compat.v2 import with_info_plain_validator_function

        return with_info_plain_validator_function(cls._validate)


class DefaultPlaceholder:
    """
    You shouldn't use this class directly.

    It's used internally to recognize when a default value has been overwritten, even
    if the overridden default value was truthy.
    """

    def __init__(self, value: Any):
        self.value = value

        Optional[Callable[..., Any]],
        Doc(
            """
            A "dependable" callable (like a function).

            Don't call it directly, FastAPI will call it for you, just pass the object
            directly.
            """
        ),
    ] = None,
    *,
    use_cache: Annotated[
        bool,
        Doc(
            """

### Eine Response direkt zurückgeben { #return-a-response-directly }

Der häufigste Anwendungsfall ist, wenn Sie [eine Response direkt zurückgeben, wie es später im Handbuch für fortgeschrittene Benutzer erläutert wird](../advanced/response-directly.md){.internal-link target=_blank}.

{* ../../docs_src/response_model/tutorial003_02_py39.py hl[8,10:11] *}

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-03-swagger-02.png)

* Click on the button "Try it out", it allows you to fill the parameters and directly interact with the API:

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-04-swagger-03.png)

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-03-swagger-02.png)

* Click on the button "Try it out", it allows you to fill the parameters and directly interact with the API:

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-04-swagger-03.png)

    * It's mainly syntax sugar, a convenience for developer experience.
    * Now `Request`, `Response`, `WebSocket`, `status` can be imported directly from `fastapi` as in `from fastapi import Response`. This is because those are frequently used, to use the request directly, to set headers and cookies, to get status codes, etc.
    * Documentation changes in many places, but new docs and noticeable improvements: