func (c *LRU[K, V]) Contains(key K) (ok bool) {
	c.mu.Lock()
	defer c.mu.Unlock()
	_, ok = c.items[key]
	return ok
}

// Peek returns the key value (or undefined if not found) without updating
// the "recently used"-ness of the key.
func (c *LRU[K, V]) Peek(key K) (value V, ok bool) {
	c.mu.Lock()
	defer c.mu.Unlock()
	var ent *Entry[K, V]
	if ent, ok = c.items[key]; ok {
		// Expired item check

```Python
async def do_something():
    try:
        yield something
    finally:
        some_cleanup()
```

...that way the `finally` block is run regardless of any exception that might happen.

### Features

    /**
     * Flag indicating an exclusive lock that prevents any other access.
     */
    public static final int SMB2_LOCKFLAG_EXCLUSIVE_LOCK = 0x2;

    /**
     * Flag indicating an unlock operation to release a previously held lock.
     */
    public static final int SMB2_LOCKFLAG_UNLOCK = 0x4;

    /**
     * Flag indicating the lock should fail immediately if it cannot be granted.
     */

	exit := func(success bool) {
		if globalLoggerOutput != nil {
			globalLoggerOutput.Close()
		}

		// If global profiler is set stop before we exit.
		globalProfilerMu.Lock()
		defer globalProfilerMu.Unlock()
		for _, p := range globalProfiler {
			p.Stop()
		}

		if success {
			os.Exit(0)
		}

		os.Exit(1)
	}

	stopProcess := func() bool {

		s.RUnlock()
		return diskID, nil
	}
	s.RUnlock()

	fi, err := s.checkFormatJSON()
	if err != nil {
		return "", err
	}

	if xioutil.SameFile(fi, fileInfo) && diskID != "" {
		s.Lock()
		// If the file has not changed, just return the cached diskID information.
		s.formatLastCheck = time.Now()
		s.Unlock()
		return diskID, nil
	}

        } finally {
            lock.writeLock().unlock();
        }
    }

    /**
     * Invalidate the cache
     */
    public void invalidate() {
        lock.writeLock().lock();
        try {
            children.clear();
            isComplete = false;
            hasChanges = true;
        } finally {
            lock.writeLock().unlock();
        }
    }

    /**

    @Override
    public void hook(final FwAssistantDirector assistantDirector) {
        processDBFluteSystem();
    }

    protected void processDBFluteSystem() {
        DBFluteSystem.unlock();
        DBFluteSystem.setFinalTimeZoneProvider(createFinalTimeZoneProvider());
        DBFluteSystem.lock();
    }

    protected DfFinalTimeZoneProvider createFinalTimeZoneProvider() {

					write([]byte(err.Error()))
				} else {
					write([]byte{0})
				}
				xioutil.SafeClose(doneCh)
				return
			case block := <-blockCh:
				var tmp [5]byte
				tmp[0] = 2
				binary.LittleEndian.PutUint32(tmp[1:], uint32(len(block)))
				write(tmp[:])
				write(block)
				if canWrite {
					xhttp.Flush(w)
				}
			}
		}
	}()
	return &h
}

	cacheStmt := &Stmt{
		Transaction: isTransaction,
		prepared:    make(chan struct{}),
	}
	// Cache the Stmt object with the associated key.
	s.Set(key, cacheStmt)
	// Unlock after completing initialization to prevent deadlocks.
	locker.Unlock()

	// Ensure the prepared channel is closed after the function execution completes.
	defer close(cacheStmt.prepared)

	// Prepare the SQL statement using the provided connection.

			defer close(lk2ch)
			nsLk.lock(ctx, "volume", "path", "source", "opsID", false, 1*time.Millisecond)
		}()
		time.Sleep(1 * time.Millisecond) // wait for goroutine to advance; ref=2

		// Unlock the 1st lock; ref=1 after this line
		nsLk.unlock("volume", "path", false)

		// Taking another lockMapMutex here allows queuing up additional lockers. This should
		// not be required but makes reproduction much easier.
		nsLk.lockMapMutex.Lock()