import threading
import time
def func_a():
print("A 开始")
time.sleep(2)
print("A 结束")
def func_b():
print("B 开始")
time.sleep(1)
print("B 结束")
创建线程
t1 = threading.Thread(target=func_a)
t2 = threading.Thread(target=func_b)
启动线程
t1.start()
t2.start()
等待两个线程都结束
t1.join()
t2.join()
print("全部完成")

def greet(name, times=1):
    for i in range(times):
        print(f"Hello, {name} ({i+1})")
        time.sleep(0.5)
t = threading.Thread(target=greet, args=("Alice",), kwargs={"times": 2})
t.start()
t.join()

threads = []
for func in [func_a, func_b, greet]:
    if func == greet:
        t = threading.Thread(target=func, args=("Bob",))
    else:
        t = threading.Thread(target=func)
    threads.append(t)
for t in threads:
t.start()
for t in threads:
t.join()

counter = 0
lock = threading.Lock()
def increment():
global counter
for _ in range(100000):
with lock:  # 自动 acquire/release
counter += 1
t1 = threading.Thread(target=increment)
t2 = threading.Thread(target=increment)
t1.start(); t2.start()
t1.join(); t2.join()
print(counter)  # 稳定输出 200000