code: def move_to(self, x, y, h):
          
          if self._has_border:
              start_x = 1
              width = self.canvas.width - 2
              start_y = self.canvas.start_line + 1
              height = self.canvas.height - 2
          else:
              start_x = 0
              width = self.canvas.width
              start_y = self.canvas.start_line
              height = self.canvas.height
  
          if ((x >= start_x) and (x < start_x + width) and
                  (y >= start_y) and (y + h < start_y + height)):
              # Already OK - quit now.
              return
  
          if y < start_y:
              self.canvas.scroll_to(y - 1 if self._has_border else y)
          else:
              line = y + h - self.canvas.height + (1 if self._has_border else 0)
              self.canvas.scroll_to(max(0, line))
docs: Make the specified location visible.  This is typically used by a widget to scroll the
          canvas such that it is visible.
  
          :param x: The x location to make visible.
          :param y: The y location to make visible.
          :param h: The height of the location to make visible.