MacBook-Air:~ huangyong$ python3

Python 3.6.1 (default, Apr  4 2017, 09:40:21)

[GCC 4.2.1 Compatible Apple LLVM 8.1.0 (clang-802.0.38)] on darwin

Type "help", "copyright", "credits" or "license" for more information.

>>> import urllib.request as ur

>>> s=ur.urlopen('https://www.zhihu.com')

>>> sl=s.read()

#略去print(sl)

>>>from bs4 import BeautifulSoup

>>> bsObj = BeautifulSoup(s.read())

#使用bsObj = BeautifulSoup(sl)的话会有警告

>>> print(bsObj.h1)

<h1 class="logo hide-text">知乎</h1>

bs4是用来给html代码分块的。

>>> f=open('test.txt','w+')

没有test.txt 会自动创建一个，python读写文件还是非常简单的。

>>> f.write(sl.decode('utf-8'))

把整个页面信息保存下来了，f.write()只能保存字符串，不解码也不能保存，

Make sure you use the right version ofpiporeasy_installfor your Python version (these may be namedpip3andeasy_install3respectively if you’re using Python 3).

pip pip3的区别是一个下载到python2.*，一个下载到python3.*