*
 * Inner classes are included because they are accessible from a value of the outer class. For example:
 *
 * ```
 * class Outer {
 *     inner class Inner
 * }
 *
 * fun foo() {
 *     val outer = Outer()
 *     outer.Inner()
 * }
 * ```
 *
 * While Kotlin always expects a constructor call when accessing `outer.Inner`, it nonetheless requires inner classes to be contained in
 * non-static scopes.
 */

  protected Queue<String> create() {
    TestQueue<String> inner = new TestQueue<>();
    Queue<String> outer = Synchronized.queue(inner, null);
    inner.mutex = outer;
    outer.add("foo"); // necessary because we try to remove elements later on
    return outer;
  }

  private static final class TestQueue<E> implements Queue<E> {
    private final Queue<E> delegate = Lists.newLinkedList();

from fastapi import FastAPI

from . import a, b

app = FastAPI()

app.include_router(a.router, prefix="/a")

from fastapi import APIRouter

router = APIRouter()


@router.get("/users/", tags=["users"])
async def read_users():
    return [{"username": "Rick"}, {"username": "Morty"}]


@router.get("/users/me", tags=["users"])
async def read_user_me():
    return {"username": "fakecurrentuser"}


@router.get("/users/{username}", tags=["users"])
async def read_user(username: str):

from fastapi import APIRouter

router = APIRouter()


@router.get("/users/", tags=["users"])
async def read_users():
    return [{"username": "Rick"}, {"username": "Morty"}]


@router.get("/users/me", tags=["users"])
async def read_user_me():
    return {"username": "fakecurrentuser"}


@router.get("/users/{username}", tags=["users"])
async def read_user(username: str):

        return custom_route_handler


app = FastAPI()
router = APIRouter(route_class=TimedRoute)


@app.get("/")
async def not_timed():
    return {"message": "Not timed"}


@router.get("/timed")
async def timed():
    return {"message": "It's the time of my life"}

### ❎ 📛 💥

👥 🏭 🔁 `items` 🔗, ↩️ 🏭 🚮 🔢 `router`.

👉 ↩️ 👥 ✔️ ➕1️⃣ 🔢 📛 `router` 🔁 `users`.

🚥 👥 ✔️ 🗄 1️⃣ ⏮️ 🎏, 💖:

```Python
from .routers.items import router
from .routers.users import router
```

`router` ⚪️➡️ `users` 🔜 📁 1️⃣ ⚪️➡️ `items` & 👥 🚫🔜 💪 ⚙️ 👫 🎏 🕰.

, 💪 ⚙️ 👯‍♂️ 👫 🎏 📁, 👥 🗄 🔁 🔗:

class InvoiceEventReceived(BaseModel):
    ok: bool


invoices_callback_router = APIRouter()


@invoices_callback_router.post(
    "{$callback_url}/invoices/{$request.body.id}", response_model=InvoiceEventReceived
)
def invoice_notification(body: InvoiceEvent):
    pass


@app.post("/invoices/", callbacks=invoices_callback_router.routes)
def create_invoice(invoice: Invoice, callback_url: Union[HttpUrl, None] = None):

            return

        wrapper = self.receive_wrapper(receive)
        await self.app(scope, wrapper, send)


@router.post("/middleware")
def run_middleware(file: UploadFile = File(..., description="Big File")):
    return {"message": "OK"}


app.include_router(router)
app.add_middleware(ContentSizeLimitMiddleware, max_content_size=2**8)


client = TestClient(app)

### 避免名称冲突

我们将直接导入 `items` 子模块，而不是仅导入其 `router` 变量。

这是因为我们在 `users` 子模块中也有另一个名为 `router` 的变量。

如果我们一个接一个地导入，例如：

```Python
from .routers.items import router
from .routers.users import router
```

来自 `users` 的 `router` 将覆盖来自 `items` 中的 `router`，我们将无法同时使用它们。

因此，为了能够在同一个文件中使用它们，我们直接导入子模块：

```Python hl_lines="5" title="app/main.py"