class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Item = Body(
        openapi_examples={
            "normal": {
                "summary": "A normal example",
                "description": "A **normal** item works correctly.",

                "put": {
                    "responses": {
                        "200": {
                            "description": "Successful Response",
                            "content": {"application/json": {"schema": {}}},
                        },
                        "422": {
                            "description": "Validation Error",
                            "content": {
                                "application/json": {

            display = ParameterDisplay.PROMPT,
            allowEmpty = true,
            description = "The baselines you want to run performance tests against. Empty means default baseline."
        )
        text(
            "testProject",
            "",
            display = ParameterDisplay.PROMPT,
            allowEmpty = false,
            description = "The test project to use. E.g. largeJavaMultiProject"
        )

                    "responses": {
                        "200": {
                            "description": "Successful Response",
                            "content": {"application/json": {"schema": {}}},
                        },
                        "422": {
                            "description": "Validation Error",
                            "content": {
                                "application/json": {

```Python
{!> ../../docs_src/separate_openapi_schemas/tutorial001.py!}
```

</details>

////

... então o campo `description` não será obrigatório. Porque ele tem um valor padrão de `None`.

### Modelo de Entrada na Documentação

Você pode confirmar que na documentação, o campo `description` não tem um **asterisco vermelho**, não é marcado como obrigatório:

<div class="screenshot">

                    "responses": {
                        "200": {
                            "description": "Successful Response",
                            "content": {"application/json": {"schema": {}}},
                        },
                        "422": {
                            "description": "Validation Error",
                            "content": {
                                "application/json": {

                    "type": "object",
                    "properties": {
                        "name": {"title": "Name", "type": "string"},
                        "description": {"title": "Description", "type": "string"},
                        "model_b": {"$ref": "#/components/schemas/ModelB"},
                    },
                },
                "ModelB": {
                    "title": "ModelB",

                        "responses": {
                            "200": {
                                "description": "Successful Response",
                                "content": {"application/json": {"schema": {}}},
                            },
                            "422": {
                                "description": "Validation Error",
                                "content": {

	}

	tests := []struct {
		description      string
		namespace        string
		defaultNamespace string
		wantNamespace    string
	}{
		{
			description:      "return test namespace",
			namespace:        "test",
			defaultNamespace: "default",
			wantNamespace:    "test",
		},
		{
			description:      "return default namespace",
			namespace:        "",

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str


items = [
    {"name": "Foo", "description": "There comes my hero"},
    {"name": "Red", "description": "It's my aeroplane"},
]


@app.get("/items/", response_model=list[Item])
async def read_items():