code: def on_epoch_begin(self, *args, **kwargs):
      super().on_epoch_begin(*args, **kwargs)
  
      # As an optimization to save tensor allocation for each
      # batch we initialize the hidden state only once per epoch.
      # This optimization was taken from the original example.
      self.hidden = self.module_.init_hidden(self.batch_size)
  
file_path: skorch/examples/word_language_model/net.py
imports: import skorch
  import numpy
  import torch
  from torch.autograd import Variable
  from sklearn.metrics import f1_score
label_desc: Use image node_id 3 for calling the Net obj's underlying member method code with example usage: obj.on_epoch_begin() without return types