from contextlib import closing
from requests import get
url = 'https://v26-web.douyinvod.com/57cdd29ee3a718825bf7b1b14d63955b/615d475f/video/tos/cn/tos-cn-ve-15/72c47fb481464cfda3d415b9759aade7/?a=6383&br=2192&bt=2192&cd=0%7C0%7C0&ch=26&cr=0&cs=0&cv=1&dr=0&ds=4&er=&ft=jal9wj--bz7ThWG4S1ct&l=021633499366600fdbddc0200fff0030a92169a000000490f5507&lr=all&mime_type=video_mp4&net=0&pl=0&qs=0&rc=ank7OzU6ZnRkNjMzNGkzM0ApNmY4aGU8MzwzNzo3ZjNpZWdiYXBtcjQwLXNgLS1kLTBzczYtNS0tMmE1Xi82Yy9gLTE6Yw%3D%3D&vl=&vr='
with closing(get(url,  stream=True)) as response:
    chunk_size = 1024  # 單次請(qǐng)求最大值
    # response.headers['content-length']得到的數(shù)據(jù)類型是str而不是int
    content_size = int(response.headers['content-length'])  # 文件總大小
    data_count = 0  # 當(dāng)前已傳輸?shù)拇笮?
    with open('文件名.mp4', "wb") as file:
        for data in response.iter_content(chunk_size=chunk_size):
            file.write(data)
            done_block = int((data_count / content_size) * 50)
            # 已經(jīng)下載的文件大小
            data_count = data_count + len(data)
            # 實(shí)時(shí)進(jìn)度條進(jìn)度
            now_jd = (data_count / content_size) * 100
            # %% 表示%
            print("\r [%s%s] %d%% " % (done_block * '█', ' ' * (50 - 1 - done_block), now_jd), end=" ")

class Door():
    def open(self):
        print('Door is opened')
    def close(self):
        print('Door is closed')
with Door() as d:
    d.open()
    d.close()

class Door():
    def open(self):
        print('Door is opened')
    def close(self):
        print('Door is closed')
with Door() as d:
    d.open()
    d.close()

class Door():
    def __enter__(self):
        print('Begin')
        return self
 
    def __exit__(self, exc_type, exc_value, traceback):
        if exc_type:
            print('Error')
        else:
            print('End')
    def open(self):
        print('Door is opened')
    def close(self):
        print('Door is closed')
with Door() as d:
    d.open()
    d.close()