code: def test_build_optimizer_simple_model(self):
      model = SimpleModel({"in_dim": 1})
      model.build()
      optimizer = build_optimizer(model, self.config)
      self.assertTrue(isinstance(optimizer, torch.optim.Optimizer))
      self.assertEqual(len(optimizer.param_groups), 1)
  
file_path: mmf/tests/modules/test_optimizers.py
imports: import gc
  import unittest
  import torch
  from mmf.models.mmbt import MMBT
  from mmf.modules.hf_layers import undo_replace_with_jit
  from mmf.utils.build import build_optimizer
  from omegaconf import OmegaConf
  from tests.test_utils import SimpleModel, skip_if_no_network
label_desc: Use image node_id 3 for calling the TestOptimizers obj's underlying member method code with example usage: obj.test_build_optimizer_simple_model() without return types