I ran this command-line on an Ubuntu 14.04 Linux while trying to install a package:

export PYTHONPATH=/usr/local/lib/python2.7/ && sudo python setup.py install

How do I revert this to the stage before running this command-line? Even starting from a fresh bash terminal, it now won't find any of my other python libraries.

Related question wasn't answered: Fixing a broken PYTHONPATH environment variable

EDIT: I don't know how to revert to the list of folders before, but I presume it was a combination of /usr/lib/python2.7 and /usr/local/lib/python2.7