if q:
        message = f"found query: {q}\n"
        background_tasks.add_task(write_log, message)
    return q


@app.post("/send-notification/{email}")
async def send_notification(
    email: str, background_tasks: BackgroundTasks, q: str = Depends(get_query)
):
    message = f"message to {email}\n"
    background_tasks.add_task(write_log, message)

@needs_py39
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1
def test_get_user(client):
    response = client.get("/users/1")
    assert response.status_code == 200, response.text
    data = response.json()
    assert "email" in data
    assert "id" in data


@needs_py39
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1
def test_nonexistent_user(client):

@needs_py310
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1
def test_get_user(client):
    response = client.get("/users/1")
    assert response.status_code == 200, response.text
    data = response.json()
    assert "email" in data
    assert "id" in data


@needs_py310
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1
def test_nonexistent_user(client):

@needs_py39
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1
def test_get_user(client):
    response = client.get("/users/1")
    assert response.status_code == 200, response.text
    data = response.json()
    assert "email" in data
    assert "id" in data


@needs_py39
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1
def test_nonexistent_user(client):

Dazu verwenden Sie `app.add_middleware()` (wie schon im Beispiel für CORS gesehen).

```Python
from fastapi import FastAPI
from unicorn import UnicornMiddleware

app = FastAPI()

app.add_middleware(UnicornMiddleware, some_config="rainbow")
```

    They are handled automatically by **FastAPI** and converted to JSON.

## Add custom headers

There are some situations in where it's useful to be able to add custom headers to the HTTP error. For example, for some types of security.

You probably won't need to use it directly in your code.

But in case you needed it for an advanced scenario, you can add custom headers:

```Python hl_lines="14"

```

✋️ FastAPI (🤙 💃) 🚚 🙅 🌌 ⚫️ 👈 ⚒ 💭 👈 🔗 🛠️ 🍵 💽 ❌ & 🛃 ⚠ 🐕‍🦺 👷 ☑.

👈, 👆 ⚙️ `app.add_middleware()` (🖼 ⚜).

```Python
from fastapi import FastAPI
from unicorn import UnicornMiddleware

app = FastAPI()

app.add_middleware(UnicornMiddleware, some_config="rainbow")
```

`app.add_middleware()` 📨 🛠️ 🎓 🥇 ❌ & 🙆 🌖 ❌ 🚶‍♀️ 🛠️.

## 🛠️ 🛠️

from fastapi import FastAPI
from fastapi.middleware.trustedhost import TrustedHostMiddleware

app = FastAPI()

app.add_middleware(
    TrustedHostMiddleware, allowed_hosts=["example.com", "*.example.com"]
)


@app.get("/")
async def main():

### `startup` event

To add a function that should be run before the application starts, declare it with the event `"startup"`:

```Python hl_lines="8"
{!../../../docs_src/events/tutorial001.py!}
```

In this case, the `startup` event handler function will initialize the items "database" (just a `dict`) with some values.

You can add more than one event handler function.

          config: >
            {
              "answered": {
                "delay": 864000,
                "message": "Assuming the original need was handled, this will be automatically closed now. But feel free to add more comments or create new issues or PRs."
              },
              "changes-requested": {
                "delay": 2628000,