code: def __call__(
      self, x: torch.Tensor, sigma: torch.Tensor
  ) -> torch.Tensor:
      x_u, x_c = x.chunk(2)
      x_pred = x_u + self.scale * (x_c - x_u)
      return x_pred
  
imports: import logging
  from abc import ABC, abstractmethod
  from typing import Dict, List, Optional, Tuple, Union
  import torch
  from einops import rearrange, repeat
  from ...util import append_dims, default
label_desc: Use image node_id 2 for calling the VanillaCFG obj's underlying member method code with example usage: obj.__call__(x, sigma) and returns: x_pred