```JSON
{
  "item": "The Foo Wrestlers"
}

```

但如果客户端请求 `http://example.com/items/bar`（`item_id` `「bar」` 不存在时），则会接收到 HTTP 状态码 - 404（「未找到」错误）及如下 JSON 响应结果：

```JSON
{
  "detail": "Item not found"
}

```

/// tip | "提示"

触发 `HTTPException` 时，可以用参数 `detail` 传递任何能转换为 JSON 的值，不仅限于 `str`。

还支持传递 `dict`、`list` 等数据结构。

    assert response.status_code == 200
    assert response.json() == snapshot(
        {"session_id": "123", "fatebook_tracker": None, "googall_tracker": None}
    )


def test_openapi_schema(client: TestClient):
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == snapshot(
        {
            "openapi": "3.1.0",

    response = client.get("/users/")
    assert response.status_code == 200, response.text


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {
            "/users/": {
                "get": {

irá verificar cada item dentro do dicionário e garantir que ele seja serializável para JSON, utilizando o mesmo[Codificador Compatível com JSON](../tutorial/encoder.md){.internal-link target=_blank} explicado no tutorial. Isso permite que você retorne **objetos abstratos**, como modelos do banco de dados, por exemplo.

Mas se você tem certeza que o conteúdo que você está retornando é **serializável com JSON**, você pode passá-lo diretamente para a classe de resposta e evitar o trabalho extra...

				formatMetaV1: formatMetaV1{
					Version: "2",
					Format:  "Erasure",
				},
				Erasure: struct {
					Version          string     `json:"version"`
					This             string     `json:"this"`
					Sets             [][]string `json:"sets"`
					DistributionAlgo string     `json:"distributionAlgo"`
				}{
					Version: "2",
				},
			},
			false,
		},
		// Invalid Erasure format "Unknown".
		{

    response = client.get(path)
    assert response.status_code == expected_status
    assert response.json() == expected_response


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {

    response = client.get(path)
    assert response.status_code == expected_status
    assert response.json() == expected_response


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {

	return ARN{TargetID: tid, region: region}
}

// MarshalJSON - encodes to JSON data.
func (tid TargetID) MarshalJSON() ([]byte, error) {
	return json.Marshal(tid.String())
}

// UnmarshalJSON - decodes JSON data.
func (tid *TargetID) UnmarshalJSON(data []byte) error {
	var s string
	if err := json.Unmarshal(data, &s); err != nil {
		return err
	}

	targetID, err := parseTargetID(s)

def test_app():
    response = client.get("/foo")
    assert response.status_code == 200, response.text


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "servers": [
            {"url": "/", "description": "Default, relative server"},

예를 들면, 위의 이 모델은 JSON "`object`" (혹은 파이썬 `dict`)을 다음과 같이 선언합니다:

```JSON
{
    "name": "Foo",
    "description": "선택적인 설명란",
    "price": 45.2,
    "tax": 3.5
}
```

...`description`과 `tax`는 (기본 값이 `None`으로 되어 있어) 선택적이기 때문에, 이 JSON "`object`"는 다음과 같은 상황에서도 유효합니다:

```JSON
{
    "name": "Foo",
    "price": 45.2
}
```

## 매개변수로서 선언하기