class_docstr: This class is adapted from the compacter implementation at https://github.com/rabeehk/compacter
code: def set_W(self, W=None, W_left=None, W_right=None):
      if self.factorized_phm_W:
          self.W_left = W_left
          self.W_right = W_right
      else:
          self.W = W
  
imports: import math
  import torch
  from torch import nn
  from transformers.activations import get_activation
  from ..configuration import AdapterFusionConfig, BnConfig
  from ..context import ForwardContext
label_desc: Use image node_id 5 for calling the PHMLayer obj's underlying member method code with example usage: obj.set_W(W, W_left, W_right) without return types