code: def _move_end_to_cxn(self, shape, cxn_pt_idx):
          
          x, y, cx, cy = shape.left, shape.top, shape.width, shape.height
          self.end_x, self.end_y = {
              0: (int(x + cx/2), y),
              1: (x, int(y + cy/2)),
              2: (int(x + cx/2), y + cy),
              3: (x + cx, int(y + cy/2)),
          }[cxn_pt_idx]
docs: Move the end point of this connector to the coordinates of the
          connection point of *shape* specified by *cxn_pt_idx*.