code: def test_lstm(self):
      args = get_default_args(GenericModel)
      args.render_image_height = 80
      args.render_image_width = 80
      args.implicit_function_class_type = "SRNImplicitFunction"
      args.renderer_class_type = "LSTMRenderer"
      args.raysampler_class_type = "NearFarRaySampler"
      args.raysampler_NearFarRaySampler_args.n_pts_per_ray_training = 1
      args.raysampler_NearFarRaySampler_args.n_pts_per_ray_evaluation = (
          1
      )
      args.renderer_LSTMRenderer_args.bg_color = [0.4, 0.4, 0.2]
      gm = GenericModel(**args)
  
      camera = PerspectiveCameras()
      image = gm.forward(
          camera=camera,
          image_rgb=None,
          fg_probability=None,
          sequence_name="",
          mask_crop=None,
          depth_map=None,
      )["images_render"]
      self.assertEqual(image.shape, (1, 3, 80, 80))
      self.assertGreater(image.max(), 0.8)
  
      # Force everything to be background
      pixel_generator = gm._implicit_functions[0]._fn.pixel_generator
      pixel_generator._density_layer.weight.zero_()
      pixel_generator._density_layer.bias.fill_(-1.0e6)
  
      image = gm.forward(
          camera=camera,
          image_rgb=None,
          fg_probability=None,
          sequence_name="",
          mask_crop=None,
          depth_map=None,
      )["images_render"]
      self.assertConstant(image[:, :2], 0.4)
      self.assertConstant(image[:, 2], 0.2)
  
file_path: pytorch3d/tests/implicitron/test_srn.py
imports: import unittest
  import torch
  from pytorch3d.implicitron.models.generic_model import GenericModel
  from pytorch3d.implicitron.models.implicit_function.scene_representation_networks import SRNHyperNetImplicitFunction, SRNImplicitFunction, SRNPixelGenerator
  from pytorch3d.implicitron.models.renderer.ray_sampler import ImplicitronRayBundle
  from pytorch3d.implicitron.tools.config import get_default_args
  from pytorch3d.renderer import PerspectiveCameras
  from tests.common_testing import TestCaseMixin
label_desc: Use image node_id 6 for calling the TestSRN obj's underlying member method code with example usage: obj.test_lstm() without return types