{* ../../docs_src/background_tasks/tutorial001.py hl[14] *}

`.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：

			if err != nil {
				err = msgp.WrapError(err)
				return
			}
		}
	}
	o = bts
	return
}

// Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message
func (z *ServerSystemConfig) Msgsize() (s int) {
	s = 1 + 11 + msgp.IntSize + 9 + msgp.ArrayHeaderSize
	for za0001 := range z.CmdLines {
		s += msgp.StringPrefixSize + len(z.CmdLines[za0001])
	}

                        else:
                            message = email.message.Message()
                            message["content-type"] = content_type_value
                            if message.get_content_maintype() == "application":
                                subtype = message.get_content_subtype()
                                if subtype == "json" or subtype.endswith("+json"):

			// report encoding bugs to AWS, and use ASCII-only metadata to ensure reliable S3 API
			// compatibility.
			if needsMimeEncoding(v) {
				// see https://github.com/golang/go/blob/release-branch.go1.24/src/net/mail/message.go#L325
				if strings.ContainsAny(v, "\"#$%&'(),.:;<>@[]^`{|}~") {
					v = mime.BEncoding.Encode("UTF-8", v)
				} else {
					v = mime.QEncoding.Encode("UTF-8", v)
				}
			}

	}
	sort.Slice(srvRecords, func(i int, j int) bool {
		return srvRecords[i].Key < srvRecords[j].Key
	})
	return srvRecords, nil
}

// Put - Adds DNS entries into etcd endpoint in CoreDNS etcd message format.
func (c *CoreDNS) Put(bucket string) error {
	c.Delete(bucket) // delete any existing entries.

	t := time.Now().UTC()
	for ip := range c.domainIPs {

	Err string
}

func (e BackendDown) Error() string {
	return e.Err
}

// NotImplemented If a feature is not implemented
type NotImplemented struct {
	Message string
}

func (e NotImplemented) Error() string {
	return e.Message
}

// UnsupportedMetadata - unsupported metadata
type UnsupportedMetadata struct{}

func (e UnsupportedMetadata) Error() string {

{* ../../docs_src/path_params/tutorial005.py hl[18,21,23] *}

Le client recevra une réponse JSON comme celle-ci :

```JSON
{
  "model_name": "alexnet",
  "message": "Deep Learning FTW!"
}
```

## Paramètres de chemin contenant des chemins

Disons que vous avez une *fonction de chemin* liée au chemin `/files/{file_path}`.

    }

    private
    fun String.assertContains(text: String) {
        assertTrue(contains(text)) {
            "Did not find expected error message in $this"
        }
    }

	conn := client.gridConn()
	if conn == nil {
		return nil
	}

	_, err := reloadSiteReplicationConfigRPC.Call(ctx, conn, grid.NewMSS())
	return err
}

// VerifyBinary - sends verify binary message to remote peers.
func (client *peerRESTClient) VerifyBinary(ctx context.Context, u *url.URL, sha256Sum []byte, releaseInfo string, reader io.Reader) error {
	values := make(url.Values)
	values.Set(peerRESTURL, u.String())

            plugin.setArtifactId(tok[1]);
            plugin.setVersion(tok[2]);
            goal.append(tok[3]);

            // This won't be valid, but it constructs something easy to read in the error message
            for (int idx = 4; idx < tok.length; idx++) {
                goal.append(":").append(tok[idx]);
            }
        } else if (numTokens == 3) {