```

=== "Python 3.8+"

    ```Python hl_lines="9"
    {!> ../../../docs_src/query_params_str_validations/tutorial002.py!}
    ```

As in this case (without using `Annotated`) we have to replace the default value `None` in the function with `Query()`, we now need to set the default value with the parameter `Query(default=None)`, it serves the same purpose of defining that default value (at least for FastAPI).

So:

Sebastián Ramírez <******@****.***> 1688149516 +0200

            if (/code|token|error/.test(window.location.hash)) {
                qp = window.location.hash.substring(1).replace('?', '&');
            } else {
                qp = location.search.substring(1);
            }

            arr = qp.split("&");
            arr.forEach(function (v,i,_arr) { _arr[i] = '"' + v.replace('=', '":"') + '"';});
            qp = qp ? JSON.parse('{' + arr.join() + '}',

```Python hl_lines="13-14  25-26"
{!../../../docs_src/extending_openapi/tutorial001.py!}
```

### Override the method

Now you can replace the `.openapi()` method with your new function.

```Python hl_lines="29"
{!../../../docs_src/extending_openapi/tutorial001.py!}
```

### Check it

```

### Utilisation du nom *path operation function* comme operationId

Si vous souhaitez utiliser les noms de fonction de vos API comme `operationId`, vous pouvez les parcourir tous et remplacer chaque `operation_id` de l'*opération de chemin* en utilisant leur `APIRoute.name`.

Vous devriez le faire après avoir ajouté toutes vos *paramètres de chemin*.

```Python hl_lines="2  12-21  24"

We are going to override the internal parts of Peewee that use `threading.local` and replace them with `contextvars`, with the corresponding updates.

This might seem a bit complex (and it actually is), you don't really need to completely understand how it works to use it.

We will create a `PeeweeConnectionState`:

            description: str | None = None

        app = FastAPI()
        router = APIRouter()

        @router.put("/items/{item_id}")
        def replace_item(item_id: str, item: Item):
            return {"message": "Item replaced", "id": item_id}

        app.include_router(router)
        ```
        """
        return self.api_route(
            path=path,

    class ModelWithDatetimeField(BaseModel):
        dt_field: datetime

        @field_serializer("dt_field")
        def serialize_datetime(self, dt_field: datetime):
            return dt_field.replace(microsecond=0, tzinfo=timezone.utc).isoformat()

    app = FastAPI()
    model = ModelWithDatetimeField(dt_field=datetime(2019, 1, 1, 8))

    @app.get("/model", response_model=ModelWithDatetimeField)
    def get_model():

    class ModelWithCustomEncoder(BaseModel):
        dt_field: datetime

        @field_serializer("dt_field")
        def serialize_dt_field(self, dt):
            return dt.replace(microsecond=0, tzinfo=timezone.utc).isoformat()

    class ModelWithCustomEncoderSubclass(ModelWithCustomEncoder):
        pass

    model = ModelWithCustomEncoder(dt_field=datetime(2019, 1, 1, 8))

And as the code related to SQLAlchemy and the SQLAlchemy models lives in separate independent files, you would even be able to perform the migrations with Alembic without having to install FastAPI, Pydantic, or anything else.

The same way, you would be able to use the same SQLAlchemy models and utilities in other parts of your code that are not related to **FastAPI**.