new_contents: """
      Remove all compiled code.
  """
  import os
  
  filedirs = ['src', 'src/sans','src/sans/perspectives', 
              'src/sans/perspectives/fitting']
  
  for d in filedirs:
      files = os.listdir(d)
      for f in files:
          if f.find('.pyc')>0:
              print "Removed", f
              os.remove(os.path.join(d,f))
subject: add clean file