title: Python PDF thumbnail preview generation
body: <p>I am looking for ways to generate jpeg thumbnail of pdf files.
  I would like to do that in Python.
  Is there any library or can anyone guide me how to do it?</p>
  
  <p>Thanks</p>
  
  <p>I am working on MacOS X Lion.
  But I would like to run it on Ubuntu or CentOS.</p>