code: def test_to_dict_recursively_changes_leaf_types(self):
      mapping_in = {"m": {"w": FlatMap(a=FlatMap(b=0))}}
      mapping_out = data_structures.to_dict(mapping_in)
      self.assertEqual(type(mapping_out["m"]["w"]), dict)
      self.assertEqual(type(mapping_out["m"]["w"]["a"]), dict)
  
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 3 for calling the DataStructuresTest obj's underlying member method code with example usage: obj.test_to_dict_recursively_changes_leaf_types() without return types