python beautifulsoup find函数连用出错

Question

import urllib2
from bs4 import BeautifulSoup
from urllib import urlretrieve

url="https://www.pythonscraping.com"
c=urllib2.urlopen(url)
soup=BeautifulSoup(c,'html.parser')
link=soup.find('a',{'id':'logo'}).find("img")

显示
Traceback (most recent call last):
File "G:/helloworld/test.py", line 9, in
link=soup.find('a',{'id':'logo'}).find("img")
AttributeError: 'NoneType' object has no attribute 'find'
不明白为什么，上网也没有找到答案，望大家帮助

Answer 1

https://www.zhihu.com/question/27728201