code: def test_only_works_on_model_params(self):
      traversal = traverse_util.ModelParamTraversal(lambda *_: True)
      with self.assertRaises(ValueError):
          list(traversal.iterate([]))
  
imports: import collections
  import jax
  import jax.numpy
  import numpy
  import optax
  from absl.testing import absltest
  import flax
  from flax import traverse_util
  from flax.core import freeze
label_desc: Use image node_id 1 for calling the ModelParamTraversalTest obj's underlying member method code with example usage: obj.test_only_works_on_model_params() without return types