requests库
import requests
url="https://img3.doubanio.com/view/subject/l/public/s33318442.jpg"
r=requests.get(url)
with open("a.jpg","wb") as f:
f.write(r.content)
urllib库
from urllib import request
# urlretrieve函数的用法
path="https://img3.doubanio.com/view/subject/l/public/s33318442.jpg"
request.urlretrieve(path,'a.jpg')
