## Eine Anwendung mit Callbacks { #an-app-with-callbacks }

Sehen wir uns das alles anhand eines Beispiels an.

Stellen Sie sich vor, Sie entwickeln eine Anwendung, mit der Sie Rechnungen erstellen können.

But then we get a `dict` in the parameter `commons` of the *path operation function*.

And we know that editors can't provide a lot of support (like completion) for `dict`s, because they can't know their keys and value types.

We can do better...

## What makes a dependency { #what-makes-a-dependency }

Up to now you have seen dependencies declared as functions.

second_user_data = {
    "id": 4,
    "name": "Mary",
    "joined": "2018-11-30",
}

my_second_user: User = User(**second_user_data)
```

/// info

`**second_user_data` şu anlama geliyor:

Key-Value çiftini direkt olarak  `second_user_data` dictionarysine kaydet , yaptığın şey buna eşit olacak: `User(id=4, name="Mary", joined="2018-11-30")`

///

### Editor desteği

### Python 3.10에서 `Union`

위의 예제에서는 `response_model` 인자 값으로 `Union[PlaneItem, CarItem]`을 전달합니다.

이 경우, 이를 **타입 어노테이션(type annotation)** 이 아닌 **인자 값(argument value)** 으로 전달하고 있기 때문에 Python 3.10에서도 `Union`을 사용해야 합니다.

만약 타입 어노테이션에 사용한다면, 다음과 같이 수직 막대(|)를 사용할 수 있습니다:

```Python
some_variable: PlaneItem | CarItem
```

	"github.com/minio/minio-go/v7/pkg/credentials"
	xhttp "github.com/minio/minio/internal/http"
	xioutil "github.com/minio/minio/internal/ioutil"
	"github.com/minio/pkg/v3/randreader"
)

// SpeedTestResult return value of the speedtest function
type SpeedTestResult struct {
	Endpoint      string
	Uploads       uint64
	Downloads     uint64
	UploadTimes   madmin.TimeDurations
	DownloadTimes madmin.TimeDurations

* Methoden.
* Request-Payloads im Body, Query-Parameter, usw.
* Response-Payloads.

Sie erhalten auch **Inline-Fehlerberichte** für alles.

type naughtyDisk struct {
	// The real disk
	disk StorageAPI
	// Programmed errors: API call number => error to return
	errors map[int]error
	// The error to return when no error value is programmed
	defaultErr error
	// The current API call number
	callNR int
	// Data protection
	mu sync.Mutex
}

func newNaughtyDisk(d StorageAPI, errs map[int]error, defaultErr error) *naughtyDisk {

	}
	if !m.checkSeq(msg.Seq) {
		return
	}
	m.recvMu.Lock()
	defer m.recvMu.Unlock()
	if cap(m.inbound) == 0 {
		m.disconnect("did not expect inbound message", true)
		return
	}
	// Note, on EOF no value can be sent.
	if msg.Flags&FlagEOF != 0 {
		if len(msg.Payload) > 0 {
			gridLogIf(m.ctx, fmt.Errorf("muxServer: EOF message with payload"))
		}
		if m.inbound != nil {
			xioutil.SafeClose(m.inbound)

	if err != nil {
		b.Fatal(err)
	}

	objSize := 128 * humanize.MiByte

	// PutObjectPart returns etag of the object inserted.
	// etag variable is assigned with that value.
	var etag string
	// get text data generated for number of bytes equal to object size.
	textData := generateBytesData(objSize)
	// generate md5sum for the generated data.

    "id": 4,
    "name": "Mary",
    "joined": "2018-11-30",
}

my_second_user: User = User(**second_user_data)
```


/// info

`**second_user_data` 意思是:

直接将`second_user_data`字典的键和值直接作为key-value参数传递，等同于：`User(id=4, name="Mary", joined="2018-11-30")`

///

### 编辑器支持

整个框架都被设计得易于使用且直观，所有的决定都在开发之前就在多个编辑器上进行了测试，来确保最佳的开发体验。