title: pip now installs to python3 not python 2.7.x
body: <p>I have Linux mint 18.x installed. When i ran pip initially it installed packages to python 2.7.x. I also installed pip3 and it handled python3 package install. But after I followed some instructions for other reasons and did apt-get update / upgrade, pip now installs to python3 and not 2.7.x. How can I reset please  as I use both. Is it a matter of rerunning:</p>
  
  <p>sudo python pip.py?</p>