!!! check "**FastAPI** uses it to"
    Handle all the data validation, data serialization and automatic model documentation (based on JSON Schema).

    **FastAPI** then takes that JSON Schema data and puts it in OpenAPI, apart from all the other things it does.

### <a href="https://www.starlette.io/" class="external-link" target="_blank">Starlette</a>

For example, let's define a variable to be a `list` of `str`.

=== "Python 3.9+"

    Declare the variable, with the same colon (`:`) syntax.

    As the type, put `list`.

    As the list is a type that contains some internal types, you put them in square brackets:

    ```Python hl_lines="1"
    {!> ../../../docs_src/python_types/tutorial006_py39.py!}
    ```

=== "Python 3.8+"

# 请求体 - 更新数据

## 用 `PUT` 更新数据

更新数据请用 <a href="https://developer.mozilla.org/zh-CN/docs/Web/HTTP/Methods/PUT" class="external-link" target="_blank">HTTP `PUT`</a> 操作。

把输入数据转换为以 JSON 格式存储的数据（比如，使用 NoSQL 数据库时），可以使用 `jsonable_encoder`。例如，把 `datetime` 转换为 `str`。

```Python hl_lines="30-35"
{!../../../docs_src/body_updates/tutorial001.py!}
```

`PUT` 用于接收替换现有数据的数据。

### 关于更新数据的警告

用 `PUT` 把数据项 `bar` 更新为以下内容时：

```Python
{

                                    }
                                )
                            }
                        },
                    },
                }
            }
        },
        "components": {
            "schemas": {
                "Body_read_items_items__item_id__put": {
                    "title": "Body_read_items_items__item_id__put",

    assert response.json() == {
        "name": "Baz",
        "description": None,
        "price": 50.2,
        "tax": 10.5,
        "tags": [],
    }


@needs_py39
def test_put(client: TestClient):
    response = client.put(
        "/items/bar", json={"name": "Barz", "price": 3, "description": None}
    )
    assert response.json() == {
        "name": "Barz",
        "description": None,
        "price": 3,

client = TestClient(app)


def test_path_operation():
    response = client.put("/get-or-create-task/foo")
    print(response.content)
    assert response.status_code == 200, response.text
    assert response.json() == "Listen to the Bar Fighters"
    response = client.put("/get-or-create-task/bar")
    assert response.status_code == 201, response.text

        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {
            "/items/{item_id}": {
                "put": {
                    "summary": "Update Item",
                    "operationId": "update_item_items__item_id__put",
                    "parameters": [
                        {
                            "required": True,

    return client


@needs_py310
def test_update(client: TestClient):
    response = client.put("/items/foo", json={"name": "Wrestlers"})
    assert response.status_code == 200, response.text
    assert response.json() == {"name": "Wrestlers", "size": None}


@needs_py310
def test_create(client: TestClient):
    response = client.put("/items/red", json={"name": "Chillies"})
    assert response.status_code == 201, response.text

    return client


@needs_py39
def test_update(client: TestClient):
    response = client.put("/items/foo", json={"name": "Wrestlers"})
    assert response.status_code == 200, response.text
    assert response.json() == {"name": "Wrestlers", "size": None}


@needs_py39
def test_create(client: TestClient):
    response = client.put("/items/red", json={"name": "Chillies"})
    assert response.status_code == 201, response.text

            ]
        }
    )


def test_put_invalid_header(client: TestClient):
    response = client.put("/items/foo", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}


def test_put(client: TestClient):
    response = client.put(