app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float = 10.5


items = {
    "foo": {"name": "Foo", "price": 50.2},
    "bar": {"name": "Bar", "description": "The Bar fighters", "price": 62, "tax": 20.2},
    "baz": {
        "name": "Baz",
        "description": "There goes my baz",
        "price": 50.2,
        "tax": 10.5,
    },
}

### 输入用的模型 { #model-for-input }

如果你像下面这样把该模型用作输入：

{* ../../docs_src/separate_openapi_schemas/tutorial001_py310.py ln[1:15] hl[14] *}

...那么 `description` 字段将**不是必填项**，因为它的默认值是 `None`。

### 文档中的输入模型 { #input-model-in-docs }

你可以在文档中确认，`description` 字段没有**红色星号**，也就是未被标记为必填：

<div class="screenshot">
<img src="/img/tutorial/separate-openapi-schemas/image01.png">
</div>

### 输出用的模型 { #model-for-output }

-   type: dropdown id: source attributes: label: Source description: Tensorflow
    installed from options: - source - binary validations: required: true

-   type: input id: tfversion attributes: label: Tensorflow Version description:
    placeholder: ex,. tf 2.8 validations: required: true

-   type: dropdown id: Code attributes: label: Custom Code description:
    options: - "Yes" - "No" validations: required: true

			Key:         config.Comment,
			Description: config.DefaultComment,
			Optional:    true,
			Type:        "sentence",
		},
		config.HelpKV{
			Key:         target.WebhookClientCert,
			Description: "client cert for Webhook mTLS auth",
			Optional:    true,
			Type:        "string",
			Sensitive:   true,
		},
		config.HelpKV{
			Key:         target.WebhookClientKey,
			Description: "client cert key for Webhook mTLS auth",

	}

	Help = config.HelpKVS{
		config.HelpKV{
			Key:         browserCSPPolicy,
			Description: `set Content-Security-Policy response header value` + defaultHelpPostfix(browserCSPPolicy),
			Optional:    true,
			Type:        "string",
		},
		config.HelpKV{
			Key:         browserHSTSSeconds,
			Description: `set Strict-Transport-Security 'max-age' amount of seconds value` + defaultHelpPostfix(browserHSTSSeconds),

          <version>3.0.0+</version>
          <required>true</required>
          <description>The full name of the project.</description>
          <type>String</type>
        </field>
        <field>
          <name>description</name>
          <version>3.0.0+</version>
          <description>A detailed description of the project, used by Maven whenever it needs to

	}

	Help = config.HelpKVS{
		config.HelpKV{
			Key:         Endpoints,
			Description: `comma separated list of etcd endpoints` + defaultHelpPostfix(Endpoints),
			Type:        "csv",
			Sensitive:   true,
		},
		config.HelpKV{
			Key:         PathPrefix,
			Description: `namespace prefix to isolate tenants` + defaultHelpPostfix(PathPrefix),
			Optional:    true,
			Type:        "path",
		},

                "price": 50.5,
                "description": "Some Foo",
                "tax": 0.1,
            },
            "user": {"username": "johndoe", "full_name": "John Doe"},
        },
    )
    assert response.status_code == 200
    assert response.json() == {
        "item_id": 5,
        "item": {
            "name": "Foo",
            "price": 50.5,
            "description": "Some Foo",
            "tax": 0.1,

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None


items = [
    Item(name="Plumbus", description="A multi-purpose household device."),
    Item(name="Portal Gun", description="A portal opening device."),
    Item(name="Meeseeks Box", description="A box that summons a Meeseeks."),
]


@app.get("/items/stream")

            "externalDocs": {
                "description": "External API documentation.",
                "url": "https://docs.example.com/api-general",
            },
            "paths": {
                "/api_route": {
                    "get": {
                        "responses": {
                            "200": {
                                "description": "Successful Response",