code: def save(self, filename):
      savedict = {
          "model": self.model.state_dict(),
          "optimizer": self.optimizer.state_dict(),
      }
      torch.save(savedict, filename)
  
imports: import torch
label_desc: Use image node_id 2 for calling the Trainer obj's underlying member method code with example usage: obj.save(filename) without return types