有进度圆周率计算

from math import*
from time import* 
scale=15
p=1
q=2
print("执行开始".center(scale//2, "-"))
start = perf_counter()
for i in range(scale+1): 
    p=sqrt((1-sqrt(1-pow(p,2)))/2)
    q=q*2
    a = ‘*‘ * i 
    b = ‘.‘ * (scale - i)
    c = (i/scale)*100 
    dur = perf_counter() - start 
    print("\r{:^3.0f}%[{}->{}]{:.2f}s".format(c,a,b,dur))
    sleep(0.1)
Pi=p*q
print("Pi值是{}".format(Pi))
print("\n"+"执行结束".center(scale//2,‘-‘))