code: def shift(self, top=None, right=None, bottom=None, left=None):
          
          polys_new = [
              poly.shift(top=top, right=right, bottom=bottom, left=left)
              for poly
              in self.polygons
          ]
          return PolygonsOnImage(polys_new, shape=self.shape)
docs: Shift all polygons from one or more image sides, i.e. move them on the x/y-axis.
  
          Parameters
          ----------
          top : None or int, optional
              Amount of pixels by which to shift all polygons from the top.
  
          right : None or int, optional
              Amount of pixels by which to shift all polygons from the right.
  
          bottom : None or int, optional
              Amount of pixels by which to shift all polygons from the bottom.
  
          left : None or int, optional
              Amount of pixels by which to shift all polygons from the left.
  
          Returns
          -------
          imgaug.PolygonsOnImage
              Shifted polygons.