)
    price: float = Field(gt=0, description="The price must be greater than zero")
    tax: Union[float, None] = None


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Annotated[Item, Body(embed=True)]):
    results = {"item_id": item_id, "item": item}

    user_in_db = UserInDB(**user_in.dict(), hashed_password=hashed_password)
    print("User saved! ..not really")
    return user_in_db


@app.post("/user/", response_model=UserOut)
async def create_user(user_in: UserIn):
    user_saved = fake_save_user(user_in)

    "item2": {
        "description": "Music is my aeroplane, it's my aeroplane",
        "type": "plane",
        "size": 5,
    },
}


@app.get("/items/{item_id}", response_model=Union[PlaneItem, CarItem])
async def read_item(item_id: str):

ut[type=file].valid{color:#468847;background:0 0;-webkit-box-shadow:none;box-shadow:none}.form-error{display:block;color:#b94a48;margin-top:5px;margin-bottom:10px;line-height:140%}span.help{color:#999;font-size:90%}input.async-validation,input.validating-server-side,select.async-validation,select.validating-server-side{opacity:.5;background-image:url(data:image/gif;base64,R0lGODlhEAAQAPQAAP///wAAAPDw8IqKiuDg4EZGRnp6egAAAFhYWCQkJKysrL6+vhQUFJycnAQEBDY2NmhoaAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA...

<summary>Of maak gebruik van <code>async def</code>...</summary>

Als je code gebruik maakt van `async` / `await`, gebruik dan `async def`:

```Python hl_lines="9  14"
from typing import Union

from fastapi import FastAPI

app = FastAPI()


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


@app.get("/items/{item_id}")

//// tab | Python 3.8+

```Python hl_lines="1"
async def needy_dependency(fresh_value: Annotated[str, Depends(get_value, use_cache=False)]):
    return {"fresh_value": fresh_value}
```

////

//// tab | Python 3.8+ nicht annotiert

/// tip | "Tipp"

Bevorzugen Sie die `Annotated`-Version, falls möglich.

///

```Python hl_lines="1"

<details markdown="1">
<summary>Tàbí lò <code>async def</code>...</summary>

Tí kóòdù rẹ̀ bá ń lò `async` / `await`, lò `async def`:

```Python hl_lines="9  14"
from typing import Union

from fastapi import FastAPI

app = FastAPI()


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


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

class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None
    tags: set[str] = set()


@app.post("/items/", response_model=Item, summary="Create an item")
async def create_item(item: Item):
    """
    Create an item with all the information:

    - **name**: each item must have a name
    - **description**: a long description
    - **price**: required

    // ThreadLocal is not available to GWT, so we always reuse the same
    // instance.  It is always safe to return the same instance because
    // javascript is single-threaded, and only used by blocks that doesn't
    // involve async callbacks.
    return CHAR_BUFFER;
  }

  private Platform() {}

import jcifs.util.transport.Response;


/**
 * @author mbechler
 *
 */
public interface CommonServerMessageBlockResponse extends CommonServerMessageBlock, Response {

    /**
     * 
     * @return is an async response
     */
    boolean isAsync ();


    /**
     * 
     * @return the next response
     */
    @Override
    CommonServerMessageBlockResponse getNextResponse ();


    /**