PS C:\Users\Administrator> python
Python 3.6.5 (v3.6.5:f59c0932b4, Mar 28 2018, 17:00:18) [MSC v.1900 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
from bs4 import BeautifulSoup
E:\Python3.6.5\lib\bs4\element.py:16: UserWarning: The soupsieve package is not installed. CSS selectors cannot be used.
'The soupsieve package is not installed. CSS selectors cannot be used.'
装一个soupsieve就可以
卸载重装python，然后cmd打开窗口，pip install beautifulsoup4,然后关掉命令行窗口，重新cmd打开，输入python,输入from bs4 import BeautifulSoup
同样的方法安装soupsieve就可以正常用了
把它装上去？
pip install soupsieve