code: def dropEvent(self, event):
          
          super(AbstractDragView, self).dropEvent(event)
          self.dragStartPosition = None
          self.dragline = None
          self.originalPos = None
          data = event.mimeData()
          stream = data.retrieveData("application/x-protocol",
              QtCore.QVariant.ByteArray)
          item = cPickle.loads(str(stream.toByteArray()))
  
          self.dropped(item, event)
  
          event.accept()
docs: Handles an item being dropped onto view, calls
          dropped -- implemented by subclass