简单进度条

import time
import sys


class Tqdm:
    def __init__(self, obj):
        self.obj = obj
        self.total = len(obj)
        self.gran = 20

    def __iter__(self):
        now = 0
        for i in self.obj:
            yield i

            now += 1
            percent = int(now / self.total * 100)
            s = f'r{percent}%' 
                f'|{"█" * (percent // (100 // self.gran)):<{self.gran}}|' 
                f' {now}/{self.total}'
            sys.stderr.write(s)


for i in Tqdm(range(100)):
    time.sleep(0.1)