code: def deflections_from_grid(self, grid):
          
          eta = np.multiply(1. / self.scale_radius, self.grid_to_grid_radii(grid=grid))
          deflection_r = np.multiply(4. * self.kappa_s * self.scale_radius, self.deflection_func_sph(eta))
  
          return self.grid_to_grid_cartesian(grid, deflection_r)
docs: Calculate the deflection angles at a given set of arc-second gridded coordinates.
  
          Parameters
          ----------
          grid : grids.RegularGrid
              The grid of (y,x) arc-second coordinates the deflection angles are computed on.