title: Run another version of Python using virtualenv
body: <p>I apologize in advance if the question is dummy ,i use Python 3.2.3 on Windows xp ,now i need Python3.3.2 , but i can't remove Python 3.2.3 because i have many codes and packages need to be run by it.<br>
  I installed virtualenv to run two versions of Python in two different environments , but after that i didn't know what to do to run a code using Python 3.3.2 , here what i did:    </p>
  
  <pre><code>C:\&gt;virtualenv.exe env1
  C:\&gt;env1\Scripts\activate
  </code></pre>
  
  <p>now i don't know what to do after a folder was created its name env1 , i downloaded Python 3.3.2 and installed it in the same folder (env1) , is that correct ? then i try the following:    </p>
  
  <pre><code>(env1) C:\&gt;python3.3.2  
  </code></pre>
  
  <p>I got the following :    </p>
  
  <pre><code>'python3.3.2' is not recognized as an internal or external command,  
  operable program or batch file. 
  </code></pre>
  
  <p>also i tried :  </p>
  
  <pre><code>(env1) C:\&gt;python python33  
  </code></pre>
  
  <p>I got the following:  </p>
  
  <pre><code>python: can't open file 'python33': [Errno 2] No such file or directory   
  </code></pre>
  
  <p>As i mentioned , i stuck at this point , any help will be very appreciated.</p>
  
  <p>Thanks</p>