code: def _lens_light_internal(self, x_grid, y_grid, kwargs_lens_light, model_bool_list=None):
          
          if model_bool_list is None:
              model_bool_list = [True] * len(kwargs_lens_light)
          lens_light = np.zeros_like(x_grid)
          for i, bool in enumerate(model_bool_list):
              if bool is True:
                  lens_light_i = self.LensLightModel.surface_brightness(x_grid, y_grid, kwargs_lens_light, k=i)
                  lens_light += lens_light_i
          return lens_light
docs: evaluates only part of the light profiles
  
          :param x_grid:
          :param y_grid:
          :param kwargs_lens_light:
          :return: