问题
Just a quick example, typing pip list doesn't work but !pip list does. Is there some syntax regarding the exclamation point and using modules in the ipython shell?
回答1:
This is actually not specific to pip, but really any shell assignment from the iPython notebook. You'll notice other shell commands also work (from the docs):
In[1]: !pwd
/User/home/
Change directory:
In[1]: !cd /var/etc
This is simply shorthand that the good folks at Jupyter have included. See Shell Assignment in the docs for more of an explanation.
来源：https://stackoverflow.com/questions/41510454/why-does-pip-need-an-exclamation-point-to-use-in-ipython