code: def forward(self, x, temb, skip_video=False, timesteps=None):
      if timesteps is None:
          timesteps = self.timesteps
  
      b, c, h, w = x.shape
  
      x = super().forward(x, temb)
  
      if not skip_video:
          x_mix = rearrange(x, "(b t) c h w -> b c t h w", t=timesteps)
  
          x = rearrange(x, "(b t) c h w -> b c t h w", t=timesteps)
  
          x = self.time_stack(x, temb)
  
          alpha = self.get_alpha(bs=b // timesteps)
          x = alpha * x + (1.0 - alpha) * x_mix
  
          x = rearrange(x, "b c t h w -> (b t) c h w")
      return x
  
imports: from typing import Callable, Iterable, Union
  import torch
  from einops import rearrange, repeat
  from sgm.modules.diffusionmodules.model import XFORMERS_IS_AVAILABLE, AttnBlock, Decoder, MemoryEfficientAttnBlock, ResnetBlock
  from sgm.modules.diffusionmodules.openaimodel import ResBlock, timestep_embedding
  from sgm.modules.video_attention import VideoTransformerBlock
  from sgm.util import partialclass
label_desc: Use image node_id 3 for calling the VideoResBlock obj's underlying member method code with example usage: obj.forward(x, temb, skip_video, timesteps) and returns: x