title: Change the pitch (and speed) of audio during playback in Python
body: <p>I'm working on a Python program that plays music. One feature will be a slider that the user can drag up or down to change the pitch of the music as it plays.</p>
  
  <p>For example, if the pitch is set to 2, then the music will sound one octave higher, it will play twice as fast, and it will last half as long. All I'm really changing is the playback speed, but I need to do so interactively in real-time.</p>
  
  <p>A good example of this functionality implemented in flash can be found <a href="http://blog.andre-michelle.com/2009/pitch-mp3/" rel="nofollow">here</a>. (It takes a little bit to load, be patient.)</p>
  
  <p>I've looked into many python audio packages, but I haven't found one that can change the pitch of a sound that is currently playing. I have multiple versions of Python, so there is no requirement for what version the package supports. I'm developing this on Windows 7.</p>
  
  <p>Any suggestions?</p>