关于使用Python的time库制作进度条程序

import time

import time
scale = 20
print("------执行开始------")
for i in range(scale+1):
    a, b = '**' * i,'..' * (scale - i)
    c = (i/scale)*100
    print("%{:^3.0f}[{}->{}]" .format (c, a, b))
    time.sleep(0.1)
print("------执行结束------")

------执行开始------
% 0 [->........................................]
% 5 [**->......................................]
%10 [****->....................................]
%15 [******->..................................]
………………………………………………         # 此处省略
%90 [************************************->....]
%95 [**************************************->..]
%100[****************************************->]
------执行结束------

import time
for i in range(101):
    print("\r{:2}%".format(i), end="")
    time.sleep(0.05)

import time
scale = 50
print("执行开始".center(scale//2,'-'))
t = time.clock()
for i in range(scale+1):
    a = '*' * i
    b = '.' * (scale - i)
    c = (i/scale)*100
    t -= time.clock()
    print("\r{:^3.0f}%[{}->{}]{:.2f}s".format(c,a,b,-t),end='')
    time.sleep(0.05)
print("\n"+"执行结束".center(scale//2,'-'))

from tqdm import tqdm
from time import sleep
for i in tqdm(range(1,100)):
    sleep(0.01)