code: def tie_weights(self):
      self.lm_head.weight = self.transformer.tokens_embeddings.weight
  
imports: import torch
  from pytorch_pretrained_bert import BertTokenizer
  from transfer_nlp.plugins.config import register_plugin
label_desc: Use image node_id 2 for calling the TransformerWithLMHead obj's underlying member method code with example usage: obj.tie_weights() without return types