ImportError: cssselect does not seem to be installed.

当使用 pip install lxml 装完lxml之后,运行程序仍会报如下错误

 'cssselect does not seem to be installed. '
ImportError: cssselect does not seem to be installed.

原因:cssselect没有安装

使用 sudo pip install cssselect

但我使用这个方法安装时出现了如下错误:

Traceback (most recent call last):
  File "/usr/bin/pip", line 9, in <module>
    from pip import main
ImportError: cannot import name main
 

后来我将sudo去掉,使用 pip install cssselect安装成功