python 使用BeautifulSoup 出错

import requests, bs4
res= requests.get(r'http://www.baidu.com')
nostarchsoup=bs4.BeautifulStoneSoup(res.text)
type(nostarchsoup)

结果显示:
UserWarning: The BeautifulStoneSoup class is deprecated. Instead of using it, pass features="xml" into the BeautifulSoup constructor.
'The BeautifulStoneSoup class is deprecated. Instead of using '

这是怎么回事呀?

nostarchsoup=bs4.BeautifulSoup(res.text，'html.parser')这样写

用bs3

 import urllib2
from BeautifulSoup import BeautifulStoneSoup #Using bs3

url="https://api.projectnimbus.org/neaodataservice.svc/NowcastSet"
request = urllib2.Request(url)
request.add_header("accept", "*/*")
request.add_header('AccountKey', "OSJeROQjTg4v7Ec3kiecjw==")
request.add_header('UniqueUserID', "00000000000000000000000000000001")
result = urllib2.urlopen(request)
xml_str = result.read()

soup = BeautifulStoneSoup(xml_str)

prop_list = []
for content in soup.findAll("m:properties"):
    props = {}
    for prop in content.findChildren():
        props[prop.name[2:]] = prop.text
    prop_list.append(props)

for prop in prop_list:
    print "Area: %(area)s\nLat: %(latitude)s\nLong: %(longitude)s\n" % prop

‘bs4.BeautifulStoneSoup’改为‘bs4.BeautifulSoup'

bs4.BeautifulSoup(res.text，'html.parser')