code: def whiten(x: torch.Tensor, subtract_mean: bool) -> torch.Tensor:
      numer = x
      if subtract_mean:
          numer -= x.mean()
      return numer / (x.std() + EPS)
  
imports: import numpy
  import torch
  import torch.nn.functional
label_desc: Use image node_id 2 for calling a global function with example usage: whiten(x, subtract_mean) and returns: unknown