code: def test_automatic_mixed_precision(self):
      model = copy.deepcopy(self.model)
      params = list(model.parameters())
      optimizer = build_optimizer(self.namespace_dls, params)
  
      self.run_iter(model, params, optimizer)
  
file_path: fairseq/tests/test_amp_optimizer.py
imports: import argparse
  import copy
  import unittest
  import torch
  from torch.cuda.amp import GradScaler, autocast
  from fairseq.optim import build_optimizer
label_desc: Use image node_id 3 for calling the TestGradientScalingAMP obj's underlying member method code with example usage: obj.test_automatic_mixed_precision() without return types