code: def test_all_null_mask(self):
      batch = input_batch.InputBatch(
          pa.RecordBatch.from_arrays(
              [
                  pa.array([[1], None, []]),
                  pa.array([[1], None, None]),
                  pa.array([[1], None, None]),
              ],
              ["f1", "f2", "f3"],
          )
      )
      path1 = types.FeaturePath(["f1"])
      path2 = types.FeaturePath(["f2"])
      path3 = types.FeaturePath(["f3"])
      expected_mask = np.array([False, True, False])
      np.testing.assert_array_equal(
          batch.all_null_mask(path1, path2, path3), expected_mask
      )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import absltest
  import numpy
  import pyarrow
  from tensorflow_data_validation import types
  from tensorflow_data_validation.statistics.generators import input_batch
label_desc: Use image node_id 5 for calling the InputBatchTest obj's underlying member method code with example usage: obj.test_all_null_mask() without return types