code: def test_traversal_set(self):
      x = {"foo": [1, 2]}
      traversal = traverse_util.t_identity["foo"].each()
      y = traversal.set([3, 4], x)
      self.assertEqual(y, {"foo": [3, 4]})
      with self.assertRaises(ValueError):
          traversal.set([3], x)  # too few values
      with self.assertRaises(ValueError):
          traversal.set([3, 4, 5], x)
  
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 14 for calling the TraversalTest obj's underlying member method code with example usage: obj.test_traversal_set() without return types