code: def test_replace_leaves_with_nodes_in_map(self):
      f = FlatMap({"foo": 1, "bar": 2})
  
      f_nested = jax.tree_util.tree_map(lambda x: {"a": (x, x)}, f)
      leaves, _ = jax.tree_util.tree_flatten(f_nested)
  
      self.assertEqual(leaves, [2, 2, 1, 1])
  
imports: import collections
  import copy
  import pickle
  import threading
  from absl.testing import absltest
  from absl.testing import parameterized
  import cloudpickle
  import dill
  from haiku._src import data_structures
  import jax
  import tree
label_desc: Use image node_id 28 for calling the FlatMappingTest obj's underlying member method code with example usage: obj.test_replace_leaves_with_nodes_in_map() without return types