class_docstr: Tests for _get_example_value_presence.
class_docstr_tok: ["Tests","for","_get_example_value_presence","."]
code: def test_example_value_presence_null_array(self):
      t = pa.RecordBatch.from_arrays(
          [
              pa.array([None, None], type=pa.null()),
          ],
          ["x"],
      )
      self.assertIsNone(
          _get_example_value_presence_as_dataframe(
              t,
              types.FeaturePath(["x"]),
              boundaries=None,
              weight_column_name=None,
          )
      )
  
imports: from typing import Optional, Sequence, Text
  from absl.testing import absltest
  import apache_beam
  import numpy
  import pandas
  import pyarrow
  from tensorflow_data_validation import types
  from tensorflow_data_validation.statistics.generators import lift_stats_generator
  from tensorflow_data_validation.utils import test_util
  from tensorflow_data_validation.utils.example_weight_map import ExampleWeightMap
  from google.protobuf import text_format
  from tensorflow_metadata.proto.v0 import schema_pb2
  from tensorflow_metadata.proto.v0 import statistics_pb2
label_desc: Use image node_id 4 for calling the GetExampleValuePresenceTest obj's underlying member method code with example usage: obj.test_example_value_presence_null_array() without return types