@app.get("/items/", response_model=list[Item], tags=["items"])
async def get_items():
    return [
        {"name": "Plumbus", "price": 3},
        {"name": "Portal Gun", "price": 9001},
    ]


@app.post("/users/", response_model=ResponseMessage, tags=["users"])
async def create_user(user: User):

```JSON hl_lines="2"
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    }
}
```

statt:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2
}
```

## Zusammenfassung { #recap }

```JSON hl_lines="2"
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    }
}
```

instead of:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2
}
```

## Recap { #recap }

    return {"message": "Item received"}


@app.get("/items/", response_model=list[Item], tags=["items"])
async def get_items():
    return [
        {"name": "Plumbus", "price": 3},
        {"name": "Portal Gun", "price": 9001},
    ]


@app.post("/users/", response_model=ResponseMessage, tags=["users"])
async def create_user(user: User):

        json={
            "importance": 2,
            "item": {"name": "Foo", "price": 50.5},
            "user": {"username": "Dave"},
        },
    )
    assert response.status_code == 200
    assert response.json() == {
        "item_id": 5,
        "importance": 2,
        "item": {
            "name": "Foo",
            "price": 50.5,
            "description": None,
            "tax": None,
        },

```Python hl_lines="2  7-10 23-25"
from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: bool | None = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: str | None = None):

from pydantic import BaseModel

app = FastAPI()


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


@app.get("/items/stream", response_class=EventSourceResponse)
async def stream_items() -> AsyncIterable[Item]:
    yield Item(name="Plumbus", price=32.99)
    yield Item(name="Portal Gun", price=999.99)
```

For full control over SSE fields (`event`, `id`, `retry`, `comment`), yield `ServerSentEvent` instances:

```JSON hl_lines="2"
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    }
}
```

ao invés de:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2
}
```

## Recapitulando { #recap }

@dataclass
class Item:
    id: uuid.UUID
    name: str
    price: float
    tags: list[str] = field(default_factory=list)
    description: str | None = None
    tax: float | None = None


app = FastAPI()


@app.get("/item", response_model=Item)
async def read_item():
    return {
        "id": uuid.uuid4(),
        "name": "Island In The Moon",
        "price": 12.99,

app = FastAPI()


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


@app.post(
    "/items/",
    summary="Create an item",
    description="Create an item with all the information, name, description, price, tax and a set of unique tags",
)
async def create_item(item: Item) -> Item: