title: Transparent window with blur behind with pyqt
body: <p>I am trying to creating a pyqt window which is semi-transparent and blurred behind.
  I have tried with setWindowOpacity to make it semi-transparent but I cannot add blur effect.
  my code is :</p>
  
  <pre><code>import sys
  from PyQt5 import QtCore, QtWidgets, QtGui
  
  
  class main(QtWidgets.QDialog):
      def __init__(self):
          super(main, self).__init__()
          self.setMinimumSize(800,500)
  
  
          self.setWindowFlags(
              self.windowFlags() | QtCore.Qt.FramelessWindowHint
          )
  
          # self.setAttribute(QtCore.Qt.WA_TranslucentBackground,on=True)
  
  
  if __name__ == "__main__":
      app = QtWidgets.QApplication(sys.argv)
      mw = main()
      mw.setWindowOpacity(.60)
      mw.show()
      sys.exit(app.exec())
  </code></pre>
  
  <p>This gives this output.</p>
  
  <p><a href="https://i.stack.imgur.com/wyCjE.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/wyCjE.jpg" alt="my output"></a></p>
  
  <p>but I want something like this :
  <a href="https://i.stack.imgur.com/nRASk.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/nRASk.jpg" alt="my imagination"></a></p>