code: def _fast_layer_norm(x, weight, bias, epsilon):
      return FastLayerNormFN.apply(x, weight, bias, epsilon)
  
imports: import torch
  from torch.nn import init
  from apex.contrib.layer_norm.layer_norm import FastLayerNormFN, FastLayerNorm
  import dropout_layer_norm
label_desc: Use image node_id 1 for calling a global function with example usage: _fast_layer_norm(x, weight, bias, epsilon) and returns: FastLayerNormFN