code: def save(self, label=None):
      # save a copy of model with label
      if label:
          self.model.save(f"{self.model_path[:-3]}-{label}.pt")
      self.model.save(self.model_path)
  
file_path: stanza/stanza/models/langid/trainer.py
imports: import torch
  import torch.optim
  from stanza.models.langid.model import LangIDBiLSTM
label_desc: Use image node_id 4 for calling the Trainer obj's underlying member method code with example usage: obj.save(label) without return types