python: 记录耗时

# 记录起始时间
start_time = time.time()

# 所需计算耗时的主程序
main()

# 计算时间差值
seconds, minutes, hours = int(time.time() - start_time), 0, 0

# 可视化打印
hours = seconds // 3600
minutes = (seconds - hours*3600) // 60
seconds = seconds - hours*3600 - minutes*60
print("\n  Complete time cost {:>02d}:{:>02d}:{:>02d}".format(hours, minutes, seconds))