code: def qteNextWindow(self):
          
          # Get the currently active window.
          win = self.qteActiveWindow()
  
          if win in self._qteWindowList:
              # Find the index of the window in the window list and
              # cyclically move to the next element in this list to find
              # the next window object.
              idx = self._qteWindowList.index(win)
              idx = (idx + 1) % len(self._qteWindowList)
              return self._qteWindowList[idx]
          else:
              msg = 'qteNextWindow method found a non-existing window.'
              self.qteLogger.warning(msg)
              return None
docs: Return next window in cyclic order.
  
          |Args|
  
          * **None**
  
          |Returns|
  
          * **QtmacsWindow**: the next window in the Qtmacs internal
              window list.
  
          |Raises|
  
          * **None**