带时间的进度条

导入time模块来计算代码运行的时间，加上代码迭代进度使用格式化字符串来输出代码运行进度

import time
scale = 50
print("执行开始，祈祷不报错".center(scale // 2,"-"))
start = time.perf_counter()
for i in range(scale + 1):
    a = "*" * i
    b = "." * (scale - i)
    c = (i / scale) * 100
    dur = time.perf_counter() - start
    print("
{:^3.0f}%[{}->{}]{:.2f}s".format(c,a,b,dur),end = "")
    time.sleep(0.1)
print("
"+"执行结束，万幸".center(scale // 2,"-"))