代码运行结果问题

# 线程的优化，线程池怎么实现
import threading
import time


def run(n):
    """线程要做的事情"""
    time.sleep(2)
    print(threading.current_thread().name, n)


def main():
    """使用传统的方法来做任务"""
    t1 = time.time()
    for n in range(10):
        run(n)
    print(time.time() - t1)


def main_use_thread():
    """使用线程优化任务"""
    # 电脑资源有限，每次最多只能跑10个线程
    t1 = time.time()
    ls = []
    for count in range(10):
        for i in range(10):
            t = threading.Thread(target=run, args=(i,))
            ls.append(t)
            t.start()

        for l in ls:
            l.join()
    print(time.time() - t1)


if __name__ == '__main__':
    # main()
    main_use_thread()

老师，代码是这样的，和老师的代码也是一样。但是运行的结果是乱七八糟的

Thread-10 9Thread-8 Thread-9 8Thread-3 2Thread-1 0Thread-4 

Thread-7 6
Thread-2 Thread-5 4

1
Thread-67

3
 5
Thread-11Thread-13 0
Thread-12 1Thread-15 4Thread-16 5
Thread-14 Thread-19 
Thread-20 98
Thread-17 6

 Thread-18 3
7
2

Thread-27Thread-25  4Thread-28 6Thread-29 8
Thread-30Thread-22Thread-21 0
7

 9

Thread-24 3
Thread-23  12

Thread-26 5
Thread-37Thread-34  Thread-40 Thread-32 1
Thread-35 43
Thread-36Thread-38 Thread-39 8

7
Thread-33 2
Thread-31 0
69

 5
Thread-41 0
Thread-45Thread-50 9
Thread-43 2Thread-48  Thread-46 5
7
Thread-44 3
Thread-49 8
4
Thread-47 6
Thread-42 1

Thread-54Thread-53 Thread-57 6Thread-59 8Thread-52Thread-56 5

Thread-60 
Thread-51 0
9 1 2


Thread-55Thread-58  47
3

Thread-63Thread-70Thread-65 4Thread-61 0Thread-68 Thread-62  9Thread-69 8
 2

Thread-64 

Thread-66 7Thread-673
51
 6


Thread-75Thread-79 8
Thread-71 Thread-77 Thread-78 7
Thread-74 0Thread-76 5
Thread-80 9
 4
Thread-72 163Thread-73 2




Thread-81Thread-86Thread-84 Thread-88 7
Thread-85Thread-89  03 Thread-87 Thread-90  4
6
Thread-82 8

9
Thread-83
 2
15

Thread-100Thread-94 3
Thread-91 Thread-98 7Thread-92 Thread-95 4
Thread-97Thread-96 
0
5Thread-93 2
 Thread-99 
1
 6
9
8
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