code: def test_persistency(self) -> None:
      feature_value_map = read_data()
      normalization_parameters = {}
      for name, values in feature_value_map.items():
          normalization_parameters[
              name
          ] = normalization.identify_parameter(
              name,
              values,
              feature_type=self._feature_type_override(name),
          )
          values[
              0
          ] = MISSING_VALUE  # Set one entry to MISSING_VALUE to test that
  
      s = normalization.serialize(normalization_parameters)
      read_parameters = normalization.deserialize(s)
      # Unfortunately, Thrift serializatin seems to lose a bit of precision.
      # Using `==` will be false.
      self.assertEqual(
          read_parameters.keys(), normalization_parameters.keys()
      )
      for k in normalization_parameters:
          self.assertEqual(
              read_parameters[k].feature_type,
              normalization_parameters[k].feature_type,
          )
          self.assertEqual(
              read_parameters[k].possible_values,
              normalization_parameters[k].possible_values,
          )
          for field in [
              "boxcox_lambda",
              "boxcox_shift",
              "mean",
              "stddev",
              "quantiles",
              "min_value",
              "max_value",
          ]:
              if getattr(normalization_parameters[k], field) is None:
                  self.assertEqual(
                      getattr(read_parameters[k], field),
                      getattr(normalization_parameters[k], field),
                  )
              else:
                  npt.assert_allclose(
                      getattr(read_parameters[k], field),
                      getattr(normalization_parameters[k], field),
                  )
  
imports: import unittest
  import numpy
  import numpy.testing
  import six
  import torch
  from reagent.preprocessing import identify_types, normalization, transforms
  from reagent.preprocessing.identify_types import BOXCOX, CONTINUOUS, DO_NOT_PREPROCESS, ENUM
  from reagent.preprocessing.normalization import MISSING_VALUE, NormalizationParameters, sort_features_by_normalization
  from reagent.preprocessing.preprocessor import Preprocessor
  from reagent.test.base.utils import NumpyFeatureProcessor
  from reagent.test.preprocessing.preprocessing_util import BOXCOX_FEATURE_ID, CONTINUOUS_FEATURE_ID, CONTINUOUS_SMALL_FEATURE_ID, ENUM_FEATURE_ID, id_to_type, PROBABILITY_FEATURE_ID, read_data
  from scipy import special
label_desc: Use image node_id 4 for calling the TestPreprocessing obj's underlying member method code with example usage: obj.test_persistency() without return types