title: PyQt4 window does not appears while running the program but appears on ipython
body: <p>I was trying out PyQt4. and tried this code.</p>
  
  <pre><code>import sys                                                                    
  from PyQt4 import QtGui                                                       
  
  app = QtGui.QApplication(sys.argv)                                            
  window = QtGui.QWidget()                                                      
  window.show()  
  print 'end'
  </code></pre>
  
  <p>This above code works when i try it on on <code>ipython</code>, But it doesn’t when i write them into a file and run it. I also tried changing the permission by <code>chmod +x</code>. The code actually runs(the reason i added a print statement at the end to confirm if the code is running till the end), i don’t get a window.</p>
  
  <p>im running python 2.7.6 on ubuntu 14.04</p>