code: def add_corners(self, image_pair, show_results=False):
          
          side = "left"
          self.object_points.append(self.corner_coordinates)
          for image in image_pair:
              corners = self._get_corners(image)
              if show_results:
                  self._show_corners(image, corners)
              self.image_points[side].append(corners.reshape(-1, 2))
              side = "right"
              self.image_count += 1
docs: Record chessboard corners found in an image pair.
  
          The image pair should be an iterable composed of two CvMats ordered
          (left, right).