code: def half_light_radius_lens(self, kwargs_lens_light, center_x=0, center_y=0, model_bool_list=None, deltaPix=None, numPix=None):
          
          if model_bool_list is None:
              model_bool_list = [True] * len(kwargs_lens_light)
          if numPix is None:
              numPix = 1000
          if deltaPix is None:
              deltaPix = 0.05
          x_grid, y_grid = util.make_grid(numPix=numPix, deltapix=deltaPix)
          x_grid += center_x
          y_grid += center_y
          lens_light = self._lens_light_internal(x_grid, y_grid, kwargs_lens_light, model_bool_list=model_bool_list)
          R_h = analysis_util.half_light_radius(lens_light, x_grid, y_grid, center_x, center_y)
          return R_h
docs: computes numerically the half-light-radius of the deflector light and the total photon flux
  
          :param kwargs_lens_light:
          :return: