from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: float = 10.5


items = {
    "foo": {"name": "Foo", "price": 50.2},
    "bar": {"name": "Bar", "description": "The Bar fighters", "price": 62, "tax": 20.2},
    "baz": {
        "name": "Baz",

                """
            ),
        ],
    ) -> None:
        """
        Move to a position in the file.

        Any next read or write will be done from that position.

        To be awaitable, compatible with async, this is run in threadpool.
        """
        return await super().seek(offset)

    async def close(self) -> None:
        """
        Close the file.

    "bar": {"id": "bar", "title": "Bar", "description": "The bartenders"},
}

app = FastAPI()


class Item(BaseModel):
    id: str
    title: str
    description: str | None = None


@app.get("/items/{item_id}", response_model=Item)
async def read_main(item_id: str, x_token: Annotated[str, Header()]):
    if x_token != fake_secret_token:

app = FastAPI()


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


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


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


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

        )

        # Update a hero
        response = client.patch(
            f"/heroes/{hero_id}", json={"name": "Dog Pond", "age": None}
        )
        assert response.status_code == 200, response.text
        assert response.json() == snapshot(
            {"name": "Dog Pond", "age": None, "id": Is(hero_id)}
        )

        # Get updated hero
        response = client.get(f"/heroes/{hero_id}")

app = FastAPI()


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


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


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


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

                DependencyScope.TEST.isTransitive(),
                byProjectPath(CommonBuilds.PROJECT_PATH_TEST)));
        result.add(internalScopeManager.createDependencyScope(
                DependencyScope.NONE.id(), DependencyScope.NONE.isTransitive(), Collections.emptySet()));
        result.add(internalScopeManager.createDependencyScope(
                DependencyScope.COMPILE_ONLY.id(),
                DependencyScope.COMPILE_ONLY.isTransitive(),

# Format: RequestType { scope:SCOPE ref:REFERENCE_TYPE }
#
# SCOPE OPTIONS:
#   session - Cache for entire Maven session (all modules in multi-module build)
#   request - Cache only for current request + its child requests
#   none    - Disable caching entirely
#
# REFERENCE OPTIONS:
#   hard - Strong reference (stays in memory, faster access)
#   soft - Weak reference (can be garbage collected under memory pressure)
#
# CONFIGURATION BREAKDOWN:

查询参数的值就是：

* `skip=20`：在 URL 中设定的值
* `limit=10`：使用默认值

## 可选参数

同理，把默认值设为 `None` 即可声明**可选的**查询参数：

{* ../../docs_src/query_params/tutorial002_py310.py hl[7] *}

本例中，查询参数 `q` 是可选的，默认值为 `None`。

/// check | 检查

注意，**FastAPI** 可以识别出 `item_id` 是路径参数，`q` 不是路径参数，而是查询参数。

///

/// note | 笔记

因为默认值为 `= None`，FastAPI 把 `q` 识别为可选参数。

                .name("defaultDispatcher")
                .message("Which dispatcher you want to use as default?");
        listPromptBuilder
                .newItem()
                .name(NONE)
                .text("None (disable MavenSecDispatcher)")
                .add();
        for (DispatcherMeta meta : secDispatcher.availableDispatchers()) {
            if (!meta.isHidden()) {
                listPromptBuilder