}
      str = builder.toString();
      HashCode hashUtf8 = murmur3_32().hashBytes(str.getBytes(Charsets.UTF_8));
      assertEquals(
          hashUtf8, murmur3_32().newHasher().putBytes(str.getBytes(Charsets.UTF_8)).hash());
      assertEquals(hashUtf8, murmur3_32().hashString(str, Charsets.UTF_8));
      assertEquals(hashUtf8, murmur3_32().newHasher().putString(str, Charsets.UTF_8).hash());

{!../../../docs_src/python_types/tutorial009.py!}
```

Использование `Optional[str]` вместо просто `str` позволит редактору помочь вам в обнаружении ошибок, в которых вы могли бы предположить, что значение всегда является `str`, хотя на самом деле это может быть и `None`.

#### Generic-типы

Эти типы принимают параметры в квадратных скобках:

* `List`
* `Tuple`
* `Set`
* `Dict`
* `Optional`
* ...и др.

from pydantic import BaseModel

app = FastAPI()


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


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int = Path(title="The ID of the item to get", ge=0, le=1000),
    q: str | None = None,
    item: Item | None = None,
):
    results = {"item_id": item_id}
    if q:

from typing import Any

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


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


@app.post("/items/", response_model=Item)
async def create_item(item: Item) -> Any:
    return item


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

⚫️ ✊ 📇 ⚗ 1️⃣ 📖 🔠 🔖.

🔠 📖 💪 🔌:

* `name` (**✔**): `str` ⏮️ 🎏 📛 👆 ⚙️ `tags` 🔢 👆 *➡ 🛠️* & `APIRouter`Ⓜ.
* `description`: `str` ⏮️ 📏 📛 🔖. ⚫️ 💪 ✔️ ✍ & 🔜 🎦 🩺 🎚.
* `externalDocs`: `dict` 🔬 🔢 🧾 ⏮️:
    * `description`: `str` ⏮️ 📏 📛 🔢 🩺.
    * `url` (**✔**): `str` ⏮️ 📛 🔢 🧾.

### ✍ 🗃 🔖

➡️ 🔄 👈 🖼 ⏮️ 🔖 `users` & `items`.

from pydantic import BaseModel, HttpUrl

app = FastAPI()


class Image(BaseModel):
    url: HttpUrl
    name: str


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None
    tags: Set[str] = set()
    images: Union[List[Image], None] = None


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item):

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


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


class User(BaseModel):
    username: str
    full_name: Union[str, None] = None


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item, user: User, importance: int = Body()):

from pydantic import BaseModel

app = FastAPI()


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


@app.put("/items/{item_id}")
async def update_item(
    item_id: Annotated[int, Path(title="The ID of the item to get", ge=0, le=1000)],
    q: str | None = None,
    item: Item | None = None,
):
    results = {"item_id": item_id}
    if q:

from fastapi.params import Body, Cookie, Depends, Header, Param, Path, Query

test_data: List[Any] = ["teststr", None, ..., 1, []]


def get_user():
    return {}  # pragma: no cover


def test_param_repr_str():
    assert repr(Param("teststr")) == "Param(teststr)"


def test_param_repr_none():
    assert repr(Param(None)) == "Param(None)"


def test_param_repr_ellipsis():
    assert repr(Param(...)) == IsOneOf(

from typing import Set, Union

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


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