code: def test_default_value():
      assert (
          huggingface_dataset_builder._default_value(
              feature_lib.Scalar(dtype=np.int32)
          )
          == -2147483648
      )
      assert (
          huggingface_dataset_builder._default_value(
              feature_lib.Scalar(dtype=np.float32)
          )
          < -3.4028234e38
      )
      sequence = feature_lib.Sequence(np.int32)
      assert (
          huggingface_dataset_builder._default_value(sequence) == []
      )  # pylint: disable=g-explicit-bool-comparison
      features_dict = feature_lib.FeaturesDict(
          {
              "foo": feature_lib.Scalar(dtype=np.str_),
          }
      )
      assert huggingface_dataset_builder._default_value(
          features_dict
      ) == {"foo": b""}
  
imports: import datetime
  from unittest import mock
  from absl import logging
  import numpy
  import pytest
  import tensorflow
  from tensorflow_datasets.core import features
  from tensorflow_datasets.core import lazy_imports_lib
  from tensorflow_datasets.core import registered
  from tensorflow_datasets.core.dataset_builders import huggingface_dataset_builder
label_desc: Use image node_id 18 for calling a global function with example usage: test_default_value() without return types