code: def __init__(
      self, dvc_model, num_pframes, loss_functions: LossFunctions
  ):
      super().__init__()
      self.model = dvc_model
      self.num_pframes = num_pframes
      if loss_functions.entropy_fn is None:
          raise ValueError(
              "Must specify entropy_fn for compression stage."
          )
      self.loss_functions = loss_functions
  
imports: from typing import Callable, NamedTuple, Optional
  import torch
  import torch.nn
  from torch import Tensor
  import neuralcompression.functional
label_desc: Use image node_id 1 to create a new DvcStage4and5 object from inherited base classes: DvcStage with example: obj = DvcStage4and5(dvc_model, num_pframes, loss_functions)