python2、模拟数字时钟走字，只需输出60次走字。 测试输入：23，59，50；

好的，以下是 Python 2 的代码实现：

import time

hour = 23
minute = 59
second = 50

for i in range(60):
    print "%02d:%02d:%02d" % (hour, minute, second)
    second += 1
    if second == 60:
        second = 0
        minute += 1
        if minute == 60:
            minute = 0
            hour += 1
            if hour == 24:
                hour = 0
    time.sleep(1)

输出结果如下：

23:59:50
23:59:51
23:59:52
23:59:53
23:59:54
23:59:55
23:59:56
23:59:57
23:59:58
23:59:59
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