In this case, the task function will write to a file (simulating sending an email).

And as the write operation doesn't use `async` and `await`, we define the function with normal `def`:

{* ../../docs_src/background_tasks/tutorial001.py hl[6:9] *}

## Add the background task

In diesem Fall schreibt die Taskfunktion in eine Datei (den Versand einer E-Mail simulierend).

Und da der Schreibvorgang nicht `async` und `await` verwendet, definieren wir die Funktion mit normalem `def`:

```Python hl_lines="6-9"
{!../../docs_src/background_tasks/tutorial001.py!}
```

## Den Hintergrundtask hinzufügen

{!../../docs_src/app_testing/tutorial001.py!}
```

/// tip

Notice that the testing functions are normal `def`, not `async def`.

And the calls to the client are also normal calls, not using `await`.

This allows you to use `pytest` directly without complications.

///

/// note | "Technical Details"

You could also use `from starlette.testclient import TestClient`.

            settingsBuilder.put("http.cors.enabled", true);
            settingsBuilder.put("discovery.type", "single-node");
        }).build(newConfigs().clusterName(clusterName).numOfNode(1));

        // wait for yellow status
        runner.ensureYellow();

        System.setProperty(FesenClient.HTTP_ADDRESS, "localhost:" + runner.node().settings().get("http.port", "9201"));

        super.setUp();
    }

    @Override

KEY:
scanner  manage namespace scanning for usage calculation, lifecycle, healing and more

ARGS:
delay     (float)     scanner delay multiplier, defaults to '10.0'
max_wait  (duration)  maximum wait time between operations, defaults to '15s'
cycle     (duration)  time duration between scanner cycles
```

            super.process(consumer);
            latch.countDown();
        }

        @Override
        public void waitForProcessed() throws InterruptedException {
            latch.await();
        }
    }

	// Alert upon this many excess object versions
	ExcessVersions int64 // 100

	// Alert upon this many excess sub-folders per folder in an erasure set.
	ExcessFolders int64 // 50000

	// MaxWait is maximum wait time between operations
	MaxWait time.Duration
	// Cycle is the time.Duration between each scanner cycles
	Cycle time.Duration
}

// DefaultKVS - default KV config for heal settings
var DefaultKVS = config.KVS{

@REM
@REM Optional ENV vars
@REM M2_HOME - location of maven2's installed home dir
@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
@REM     e.g. to debug Maven itself, use
@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000

				mu.Lock()
				if _, ok := healBuckets[volInfo.Name]; !ok {
					healBuckets[volInfo.Name] = volInfo
				}
				mu.Unlock()
			}
			return nil
		}, index)
	}
	return reduceReadQuorumErrs(ctx, g.Wait(), bucketMetadataOpIgnoredErrs, readQuorum)
}

var errLegacyXLMeta = errors.New("legacy XL meta")

var errOutdatedXLMeta = errors.New("outdated XL meta")

def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">
<summary>⚖️ ⚙️ <code>async def</code>...</summary>

🚥 👆 📟 ⚙️ `async` / `await`, ⚙️ `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"}