title: How to set default python version for pip?
body: <p>OS: Mac OS X 10.11.3</p>
  
  <p>I have Python 2.7.10 and Python 3.4.3.</p>
  
  <p>When I <code>pip install some_package</code> pip installs package for Python 2.7.10, but I want to install package for Python 3.4.3.</p>
  
  <p>How I can set default Python or install package for 3.4.3?</p>