I'm running into an error where when I try 
from PIL import Image, ImageFilter
in a Python file I get an error stating ModuleNotFoundError: No module named 'PIL'.
So far I've tried uninstalling/reinstalling both PIL and Pillow, along with just doing import Image, but the error keeps on occurring and I have no idea why. All the solutions I've found so far have had no effect on my issue. 
I'm running Python 3.5 on Ubuntu 16.04
Alright, I found a fix 
To fix the issue, I uninstalled PIL and Pillow through sudo pip3 uninstall pillow and sudo apt-get purge python3-pil. I then restarted and then used sudo -H pip3 install pillow to reinstall Pillow 
The only step I was missing before was rebooting, and not reinstalling PIL afterwards. 
It seems to have worked without any issues so far.
No module named 'PIL'