Example:

        «««
        ```
        Hello
        World
        ```
        »»»

    Example:

        «««
        ```python
        print("hello World")
        ```
        »»»

"HTML element"

input size | lib | MB/s | Allocated
--- | --- | --- | ---
regular | standard | 97 | 3.6MB
regular | jstream | 175 | 2.1MB
large | standard | 92 | 305MB
large | jstream | 404 | 69MB

In a real world scenario, including initialization and reader overhead from varying blob sizes, performance can be expected as below:

### 创建

* 创建一个 `main.py` 文件并写入以下内容:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

{* ../../docs_src/custom_response/tutorial009c_py39.py hl[9:14,17] *}

Теперь вместо того, чтобы возвращать:

```json
{"message": "Hello World"}
```

...этот ответ вернёт:

```json
{
  "message": "Hello World"
}
```

Разумеется, вы наверняка найдёте гораздо более полезные способы воспользоваться этим, чем просто форматирование JSON. 😉

            package org.apache.maven.samples.sample;

            public class App {
                public static void main(String... args) {
                    System.out.println("Hello World!");
                }
            }
            """;

    protected Map<String, String> invoke(Path cwd, Path userHome, Collection<String> goals, Collection<String> args)
            throws Exception {

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

	errFatal(local.RegisterStreamingHandler(handlerTest2, h2))

	// local to remote
	remoteConn := local.Connection(remoteHost)
	errFatal(remoteConn.WaitForConnect(t.Context()))
	const testPayload = "Hello Grid World!"

	gotResp := make(chan struct{})
	go func() {
		start := time.Now()
		t.Log("Roundtrip: sending request")
		resp, err := remoteConn.Request(t.Context(), handlerTest, []byte(testPayload))

  public void testWrap() {
    new EqualsTester()
        .addEqualityGroup(
            LENGTH_EQUIVALENCE.wrap("hello"),
            LENGTH_EQUIVALENCE.wrap("hello"),
            LENGTH_EQUIVALENCE.wrap("world"))
        .addEqualityGroup(LENGTH_EQUIVALENCE.wrap("hi"), LENGTH_EQUIVALENCE.wrap("yo"))
        .addEqualityGroup(
            LENGTH_EQUIVALENCE.<@Nullable String>wrap(null),

{* ../../docs_src/custom_response/tutorial009c.py hl[9:14,17] *}

이제 다음 대신:

```json
{"message": "Hello World"}
```

이 응답은 이렇게 반환됩니다:

```json
{
  "message": "Hello World"
}
```

물론 JSON 포맷팅보다 더 유용하게 활용할 방법을 찾을 수 있을 것입니다. 😉

## 기본 응답 클래스

**FastAPI** 클래스 객체 또는 `APIRouter`를 생성할 때 기본적으로 사용할 응답 클래스를 지정할 수 있습니다.

Erstellen Sie eine Datei `main.py` mit:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">