code: def setup(self):
      self.model = torch.nn.Linear(1, 1)
      self.optimizer = torch.optim.SGD(self.model.parameters(), lr=0.1)
  
file_path: ray/python/ray/air/examples/custom_trainer.py
imports: import torch
  from ray import train
  from ray.train.trainer import BaseTrainer
  import ray
label_desc: Use image node_id 1 for calling the MyPytorchTrainer obj's underlying member method code with example usage: obj.setup() without return types