title: How to change version of Python picked up by Cygwin
body: <p>I have two versions of python installed on Win7. (Python 2.5 and Python 2.7).</p>
  
  <p>These are located in 'C:/Python25' and 'C:/Python27' respectively.</p>
  
  <p>I am trying to run a file using Python 2.5 but by default Cygwin picks up 2.7.</p>
  
  <p>How do I change which version Cygwin uses?</p>