/// info | 信息

方括号中的这些内部类型称为“类型参数”（type parameters）。

在这个例子中，`str` 是传给 `list` 的类型参数。

///

这表示：“变量 `items` 是一个 `list`，并且列表中的每一个元素都是 `str`”。

这样，即使是在处理列表中的元素时，编辑器也能给你提供支持：

<img src="/img/python-types/image05.png">

没有类型的话，这几乎是不可能做到的。

注意，变量 `item` 是列表 `items` 中的一个元素。

即便如此，编辑器仍然知道它是 `str`，并为此提供支持。

#### 元组和集合 { #tuple-and-set }

声明 `tuple` 和 `set` 的方式类似：

from sqlmodel import Field, Session, SQLModel, create_engine, select


class Hero(SQLModel, table=True):
    id: int | None = Field(default=None, primary_key=True)
    name: str = Field(index=True)
    age: int | None = Field(default=None, index=True)
    secret_name: str


sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"

connect_args = {"check_same_thread": False}

DecoratedCallable = TypeVar("DecoratedCallable", bound=Callable[..., Any])
UnionType = getattr(types, "UnionType", Union)
ModelNameMap = dict[type[BaseModel] | type[Enum], str]

  }

  @Override
  public void write(char[] cbuf, int off, int len) throws IOException {
    super.write(cbuf, off, len);
    flush();
  }

  @Override
  public void write(String str, int off, int len) throws IOException {
    super.write(str, off, len);
    flush();
  }

  public boolean closed() {
    return out.closed();
  }

    SpliteratorTester.of(
            () ->
                CollectSpliterators.flatMap(
                    Arrays.spliterator(new String[] {"abc", "", "de", "f", "g", ""}),
                    (String str) -> str.isEmpty() ? null : charactersOf(str).spliterator(),
                    Spliterator.SIZED | Spliterator.DISTINCT | Spliterator.NONNULL,
                    7))
        .expect('a', 'b', 'c', 'd', 'e', 'f', 'g');
  }

class HeroBase(SQLModel):
    name: str = Field(index=True)
    age: int | None = Field(default=None, index=True)


class Hero(HeroBase, table=True):
    id: int | None = Field(default=None, primary_key=True)
    secret_name: str


class HeroPublic(HeroBase):
    id: int


class HeroCreate(HeroBase):
    secret_name: str


class HeroUpdate(HeroBase):
    name: str | None = None

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])

    AtomicInteger deliveries = new AtomicInteger();
    EventBus bus = new EventBus();
    bus.register(
        new Object() {
          @Subscribe
          public void accept(String str) {
            holder.set(str);
            deliveries.incrementAndGet();
          }
        });

    String EVENT = "Hello!";
    bus.post(EVENT);

    assertEquals("Only one event should be delivered.", 1, deliveries.get());

    authorizationUrl="authorize",
    tokenUrl="token",
    auto_error=True,
    scopes={"read": "Read access", "write": "Write access"},
)


async def get_token(token: Annotated[str, Depends(oauth2_scheme)]) -> str:
    return token


app = FastAPI(dependencies=[Depends(get_token)])


@app.get("/")
async def root():
    return {"message": "Hello World"}


@app.get(

        app = FastAPI()

        class Item(BaseModel):
            title: str

        @app.get("/items/{id}")
        def read_items(id: list[Item]):
            pass  # pragma: no cover


def test_invalid_tuple():
    with pytest.raises(AssertionError):
        app = FastAPI()

        class Item(BaseModel):
            title: str

        @app.get("/items/{id}")
        def read_items(id: tuple[Item, Item]):