code: def shift(self, x=0, y=0):
          
          keypoints = [keypoint.shift(x=x, y=y) for keypoint in self.keypoints]
          return self.deepcopy(keypoints)
docs: Move the keypoints around on an image.
  
          Parameters
          ----------
          x : number, optional
              Move each keypoint by this value on the x axis.
  
          y : number, optional
              Move each keypoint by this value on the y axis.
  
          Returns
          -------
          out : KeypointsOnImage
              Keypoints after moving them.