Note over client,operation: Response is already sent, can't change it anymore
    opt Tasks
        operation -->> tasks: Send background tasks
    end
    opt Raise other exception
        tasks -->> tasks: Handle exceptions in the background task code
    end
```

/// info

클라이언트에는 **하나의 응답**만 전송됩니다. 이는 오류 응답 중 하나일 수도 있고, *경로 처리*에서 생성된 응답일 수도 있습니다.

    Note over client,operation: Response is already sent, can't change it anymore
    opt Tasks
        operation -->> tasks: Send background tasks
    end
    opt Raise other exception
        tasks -->> tasks: Handle exceptions in the background task code
    end
```

/// info

只會向用戶端送出「一個回應」。可能是其中一個錯誤回應，或是來自該路徑操作的回應。

一旦送出了其中一個回應，就不能再送出其他回應。

///

/// tip

async def send_notification(email: str, background_tasks: BackgroundTasks):
    background_tasks.add_task(write_notification, email, message="some notification")

            : new DirectStarter();
  }

  /** The actual reference queue that our background thread will poll. */
  final ReferenceQueue<Object> queue;

  final PhantomReference<Object> frqRef;

  /** Whether or not the background thread started successfully. */
  final boolean threadStarted;

  /** Constructs a new queue. */
  public FinalizableReferenceQueue() {

        os.remove(log)  # pragma: no cover
    response = client.post("/send-notification/******@****.***")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Notification sent in the background"}
    with open("./log.txt") as f:

            : new DirectStarter();
  }

  /** The actual reference queue that our background thread will poll. */
  final ReferenceQueue<Object> queue;

  final PhantomReference<Object> frqRef;

  /** Whether or not the background thread started successfully. */
  final boolean threadStarted;

  /** Constructs a new queue. */
  public FinalizableReferenceQueue() {

"""FastAPI framework, high performance, easy to learn, fast to code, ready for production"""

__version__ = "0.135.3"

from starlette import status as status

from .applications import FastAPI as FastAPI
from .background import BackgroundTasks as BackgroundTasks
from .datastructures import UploadFile as UploadFile
from .exceptions import HTTPException as HTTPException
from .exceptions import WebSocketException as WebSocketException

	// Simulate the concurrent scenario from the original race condition:
	// Multiple HTTP request handlers updating stats concurrently,
	// while background processes are reading the stats for persistence.
	const numWriters = 100 // Simulate many HTTP request handlers.
	const numReaders = 50  // Simulate background stats readers.
	const opsPerGoroutine = 100

	var wg sync.WaitGroup
	for i := range numWriters {
		wg.Add(1)
		go func(writerID int) {

import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import org.jspecify.annotations.Nullable;

/**
 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible

import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import org.jspecify.annotations.Nullable;

/**
 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible