import threading import time def print_numbers(x): for i in range(5): time.sleep(1) print(f"Thread {x}: {i}") # 串行测试 start_time = time.time() print_numbers('A') print_numbers('B') end_time = time.time() print(end_time - start_time, '\n') # 创建两个线程 thread1 = threading.Thread(target=print_numbers, args=('A')) thread2 = threading.Thread(target=print_numbers, args=('B')) start_time = time.time() # 启动线程 thread1.start() thread2.start() # 等待两个线程完成 thread1.join() thread2.join() end_time = time.time() print(end_time - start_time)