Maybe wrong BS version?

    $ sudo pip install BeautifulSoup
    Downloading/unpacking BeautifulSoup
      Downloading BeautifulSoup-3.2.1.tar.gz
      Running setup.py (path:/tmp/pip_build_root/BeautifulSoup/setup.py) egg_info for package BeautifulSoup
        
    Installing collected packages: BeautifulSoup
      Running setup.py install for BeautifulSoup
        
    Successfully installed BeautifulSoup
    Cleaning up...