code: def blurring_mask_for_psf_shape(self, psf_shape):
          
  
          if psf_shape[0] % 2 == 0 or psf_shape[1] % 2 == 0:
              raise exc.MaskException("psf_size of exterior region must be odd")
  
          blurring_mask = mask_util.mask_blurring_from_mask_and_psf_shape(self, psf_shape)
  
          return Mask(blurring_mask, self.pixel_scale)
docs: Compute a blurring mask, which represents all masked pixels whose light will be blurred into unmasked \
          pixels via PSF convolution (see grid_stack.RegularGrid.blurring_grid_from_mask_and_psf_shape).
  
          Parameters
          ----------
          psf_shape : (int, int)
             The shape of the psf which defines the blurring region (e.g. the shape of the PSF)