response = client.put(
        "/items/5",
        json={
            "importance": 2,
            "item": {"name": "Foo", "price": 50.5},
            "user": {"username": "Dave"},
        },
        params={"q": "somequery"},
    )
    assert response.status_code == 200
    assert response.json() == {
        "item_id": 5,
        "importance": 2,
        "item": {
            "name": "Foo",

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None
    tags: set[str] = set()


@app.post("/items/", response_model=Item, tags=["items"])
async def create_item(item: Item):
    return item


@app.get("/items/", tags=["items"])
async def read_items():
    return [{"name": "Foo", "price": 42}]

                            }
                        },
                        "required": True,
                    },
                },
            }
        },
        "components": {
            "schemas": {
                "Item": {
                    "type": "object",
                    "title": "Item",
                    "properties": {

def test_path_operation():
    response = client.get("/items/foo")
    assert response.status_code == 200, response.text
    assert response.json() == {"id": "foo", "value": "there goes my hero"}


def test_path_operation_not_found():
    response = client.get("/items/bar")
    assert response.status_code == 404, response.text
    assert response.json() == {"message": "Item not found"}


def test_openapi_schema():

{* ../../docs_src/pydantic_v1_in_v2/tutorial003_an_py310.py hl[2:3,6,12,21:22] *}

In this example above, the input model is a Pydantic v1 model, and the output model (defined in `response_model=ItemV2`) is a Pydantic v2 model.

### Pydantic v1 parameters { #pydantic-v1-parameters }

class Item(BaseModel):
    name: str
    price: float


class ResponseMessage(BaseModel):
    message: str


class User(BaseModel):
    username: str
    email: str


@app.post("/items/", response_model=ResponseMessage, tags=["items"])
async def create_item(item: Item):
    return {"message": "Item received"}


@app.get("/items/", response_model=list[Item], tags=["items"])

                    },
                    "summary": "Create an item",
                    "description": "Create an item with all the information:\n\n- **name**: each item must have a name\n- **description**: a long description\n- **price**: required\n- **tax**: if the item doesn't have tax, you can omit this\n- **tags**: a set of unique tag strings for this item",
                    "operationId": "create_item_items__post",

def process_items(items: list[str]):
    for item in items:

                    "properties": {
                        "name": {"title": "Name", "type": "string"},
                        "items": {
                            "title": "Items",
                            "type": "array",
                            "items": {"$ref": "#/components/schemas/Item"},
                        },
                    },
                },
                "HTTPValidationError": {

        "paths": {
            "/items/": {
                "post": {
                    "summary": "Create Item",
                    "operationId": "create_item_items__post",
                    "requestBody": {
                        "content": {
                            "application/x-yaml": {
                                "schema": {
                                    "title": "Item",