code: def on_test_epoch_end(self):
      save_path = os.path.join(self.trainer.log_dir, "test")
      os.makedirs(save_path, exist_ok=True)
  
      images = np.concatenate(self.test_images, axis=0)
      imageio.mimwrite(
          os.path.join(
              os.path.join(
                  save_path,
                  f"{self.current_epoch:04d}_{self.global_step:04d}_rgb.mp4",
              )
          ),
          images,
          fps=25,
          quality=8,
          macro_block_size=1,
      )
  
      depths = np.concatenate(self.test_depths, axis=0)
      imageio.mimwrite(
          os.path.join(
              os.path.join(
                  save_path,
                  f"{self.current_epoch:04d}_{self.global_step:04d}_depth.mp4",
              )
          ),
          depths,
          fps=25,
          quality=8,
          macro_block_size=1,
      )
  
      self.test_images.clear()
      self.test_depths.clear()
  
imports: import os
  import random
  import cv2
  import imageio
  import numpy
  import torch
  from nemo.collections.multimodal.models.nerf.txt2nerf_base import Txt2NerfBase
  from nemo.collections.multimodal.modules.nerf.loss.laplacian_smooth_loss import LaplacianSmoothLoss
  from nemo.collections.multimodal.modules.nerf.loss.normal_consistency_loss import NormalConsistencyLoss
  from nemo.collections.multimodal.modules.nerf.materials.materials_base import ShadingEnum
  from nemo.core import optim
label_desc: Use image node_id 5 for calling the DreamFusion obj's underlying member method code with example usage: obj.on_test_epoch_end() without return types