code: def test_recursive_map(self):
      arr = [[[1], [2], [3]]]
      arr_str = list(recursive_map(arr, str))
  
      self.assertEqual(arr_str[0][0][0], "1")
  
imports: import json
  import os
  import random
  import shutil
  import tempfile
  import unittest
  import numpy
  import torch
  from pytext.utils import recursive_map, round_seq, set_random_seeds
  from pytext.utils.data import align_slot_labels, merge_token_labels_to_slot, strip_bio_prefix, unkify
  from pytext.utils.distributed import get_shard_range
  from pytext.utils.file_io import chunk_file, PathManager
  from pytext.utils.meter import TimeMeter
  from pytext.utils.test import import_tests_module
label_desc: Use image node_id 8 for calling the UtilTest obj's underlying member method code with example usage: obj.test_recursive_map() without return types