为什么会报错
from bs4 import beautifulSoup
html_doc = """
<html><head><title>The Dormouse's story</title></head>
<p class="title"><b>The Dormouse's story</b></p>
<p class="story">Once upon a time there were three little sisters; and their names were
<a href="http://example.com/elsie" class="sister" id="link1">Elsie</a>,
<a href="http://example.com/lacie" class="sister" id="link2">Lacie</a> and
<a href="http://example.com/tillie" class="sister" id="link3">Tillie</a>;
and they lived at the bottom of a well.</p>
<p class="story">...</p>
"""
soup=beautifulsoup(html_doc,'html_doc',from_encoding='utf-8')
links=soup.find_all('a')
for link in links:
print link.name,link['href'],link.get_text()
报错：
Traceback (most recent call last):
File "C:\eclipse\imooc\com\imooc\helloworld.py", line 1, in <module>
from bs4 import beautifulSoup
ImportError: cannot import name beautifulSoup
