code: def forward(self,pixx,pixy):
          
          # This matches WTRAXY results to better than 1e-4 pixels.
          skyx,skyy = self.input.all_pix2world(pixx,pixy,self.origin)
          result= self.output.wcs_world2pix(skyx,skyy,self.origin)
          return result
docs: Transform the input pixx,pixy positions in the input frame
              to pixel positions in the output frame.
  
              This method gets passed to the drizzle algorithm.