* Любое упорядоченное количество аргументов, которые принимает функция (`email`).
* Любое количество именованных аргументов, которые принимает функция (`message="some notification"`).

## Встраивание зависимостей

copyright law: that is to say, a work containing the Library or a
portion of it, either verbatim or with modifications and/or translated
straightforwardly into another language.  (Hereinafter, translation is
included without limitation in the term "modification".)

  "Source code" for a work means the preferred form of the work for
making modifications to it.  For a library, complete source code means

 * implementation can be created easily by extending this class and implementing the {@link
 * Multiset#entrySet()} method, plus optionally overriding {@link #add(Object, int)} and {@link
 * #remove(Object, int)} to enable modifications to the multiset.
 *
 * <p>The {@link #count} and {@link #size} implementations all iterate across the set returned by
 * {@link Multiset#entrySet()}, as do many methods acting on the set returned by {@link

	cred, _, _ = getReqAccessKeyV4(r, region, serviceS3)
	if cred.AccessKey == "" {
		cred, _, _ = getReqAccessKeyV2(r)
	}
	return cred
}

// Extract request params to be sent with event notification.
func extractReqParams(r *http.Request) map[string]string {
	if r == nil {
		return nil
	}

	region := globalSite.Region()
	cred := getReqAccessCred(r, region)

	principalID := cred.AccessKey

						</ul>
					</div>
				</div>
			</nav>
		</header>

		<main id="content" class="container">
			<h2>
				<la:message key="labels.advance_search_title" />
			</h2>
			<div class="notification">${notification}</div>
			<div>
				<la:info id="msg" message="true">
					<div class="alert alert-info">${msg}</div>
				</la:info>

				"application/vnd.symbian.install",
				"application/vnd.syncml+xml",
				"application/vnd.syncml.dm+wbxml",
				"application/vnd.syncml.dm+xml",
				"application/vnd.syncml.dm.notification",
				"application/vnd.syncml.ds.notification",
				"application/vnd.tao.intent-module-archive",
				"application/vnd.tcpdump.pcap",
				"application/vnd.tmobile-livetv",
				"application/vnd.trid.tpt",
				"application/vnd.triscape.mxs",

	auditCollectorPath         collectorPath = "/audit"
	loggerWebhookCollectorPath collectorPath = "/logger/webhook"
	replicationCollectorPath   collectorPath = "/replication"
	notificationCollectorPath  collectorPath = "/notification"
	scannerCollectorPath       collectorPath = "/scanner"
)

const (
	clusterBasePath = "/cluster"
)

type metricsV3Collection struct {
	mgMap       map[collectorPath]*MetricsGroup

		return nil, time.Time{}, BucketLifecycleNotFound{Bucket: bucket}
	}
	return meta.lifecycleConfig, meta.LifecycleConfigUpdatedAt, nil
}

// GetNotificationConfig returns configured notification config
// The returned object may not be modified.
func (sys *BucketMetadataSys) GetNotificationConfig(bucket string) (*event.Config, error) {
	meta, _, err := sys.GetConfig(GlobalContext, bucket)
	if err != nil {

```Python hl_lines="14"
{!../../docs_src/background_tasks/tutorial001.py!}
```

`.add_task()` 接收以下参数：

* 在后台运行的任务函数(`write_notification`)。
* 应按顺序传递给任务函数的任意参数序列(`email`)。
* 应传递给任务函数的任意关键字参数(`message="some notification"`)。

## 依赖注入

使用 `BackgroundTasks` 也适用于依赖注入系统，你可以在多个级别声明 `BackgroundTasks` 类型的参数：在 *路径操作函数* 里，在依赖中(可依赖)，在子依赖中，等等。

**FastAPI** 知道在每种情况下该做什么以及如何复用同一对象，因此所有后台任务被合并在一起并且随后在后台运行：

//// tab | Python 3.10+

* Eine beliebige Folge von Argumenten, die der Reihe nach an die Taskfunktion übergeben werden sollen (`email`).
* Alle Schlüsselwort-Argumente, die an die Taskfunktion übergeben werden sollen (`message="some notification"`).

## Dependency Injection