怎样在Python中实现线程同步？

import threading

# 共享资源
counter = 0

# 锁对象
lock = threading.Lock()

def increment():
    global counter
    for _ in range(100000):
        with lock:  # 获得锁
            counter += 1  # 增加计数器
        # 锁会在这里自动释放

# 创建两个线程
thread1 = threading.Thread(target=increment)
thread2 = threading.Thread(target=increment)

# 启动线程
thread1.start()
thread2.start()

# 等待线程完成
thread1.join()
thread2.join()

print(f"最终计数器值: {counter}")

import threading

rlock = threading.RLock()

def nested_function():
    with rlock:
        print("获得锁")
        with rlock:
            print("再次获得锁")

thread = threading.Thread(target=nested_function)
thread.start()
thread.join()

import threading
import time

semaphore = threading.Semaphore(5)

def worker():
    with semaphore:
        print(f"线程 {threading.current_thread().name} 进入池子")
        time.sleep(2)
        print(f"线程 {threading.current_thread().name} 离开池子")

threads = []
for i in range(10):
    t = threading.Thread(target=worker, name=f"Thread-{i}")
    threads.append(t)
    t.start()

for t in threads:
    t.join()

import threading
import time
import random

items = []
condition = threading.Condition()

def producer():
    global items
    while True:
        with condition:
            if len(items) == 10:
                condition.wait()
            item = random.randint(1, 10)
            items.append(item)
            print(f"生产者添加了{item}")
            condition.notify()

def consumer():
    global items
    while True:
        with condition:
            if len(items) == 0:
                condition.wait()
            item = items.pop(0)
            print(f"消费者消费了{item}")
            condition.notify()
        time.sleep(1)

producer_thread = threading.Thread(target=producer)
consumer_thread = threading.Thread(target=consumer)

producer_thread.start()
consumer_thread.start()

producer_thread.join()
consumer_thread.join()

import threading
import time

event = threading.Event()

def worker():
    print("等待事件...")
    event.wait()
    print("事件已触发，继续执行")

thread = threading.Thread(target=worker)
thread.start()

time.sleep(2)
print("触发事件")
event.set()

thread.join()