用Python算带有进度条的圆周率

 import time
 scale=50
 print("执行开始".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("\r{:3.0f}%[{}->{}]{:.2f}s".format(c,a,b,dur),end=" ")
     time.sleep(0.1)
 print("\n"+"执行结束".center(scale//2,"-"))