def ScrollUp(self, units):
         """Move view up number of axis units."""
         self.last_PointLabel = None        #reset pointLabel
-        if self.last_draw is not None:         
+        if self.last_draw is not None:
              graphics, xAxis, yAxis= self.last_draw
              yAxis= (yAxis[0]+units, yAxis[1]+units)
              self.Draw(graphics,xAxis,yAxis)