code: def test_top_level(self):
      f = features_lib.FeaturesDict(
          {
              "a": np.int32,
              "b": {
                  "c": np.int32,
              },
          }
      )
  
      # Only top level can be decoded
      f.decode_example(
          {
              "a": 1,
              "b": {
                  "c": 2,
              },
          }
      )
      f.decode_example_np(
          {
              "a": 1,
              "b": {
                  "c": 2,
              },
          }
      )
  
file_path: datasets/tensorflow_datasets/core/features/top_level_feature_test.py
imports: import time
  import numpy
  from tensorflow_datasets import testing
  from tensorflow_datasets.core import features
  from tensorflow_datasets.core.features import top_level_feature
label_desc: Use image node_id 3 for calling the FeaturesManagerTest obj's underlying member method code with example usage: obj.test_top_level() without return types