An error message says, "You are trying to run the Python 2 version of BS under Python 3."
I have no idea how to make BS4 work on my Python 3.
Install BeautifulSoup with pip instead of whatever way you did.
pip3 install bs4
Output:
metulburr@ubuntu:~$ pip3 install bs4
Requirement already satisfied: bs4 in /usr/local/lib/python3.6/site-packages
Requirement already satisfied: beautifulsoup4 in /usr/local/lib/python3.6/site-packages (from bs4)
Thank you so much for the help!