code: def _preprocessing_fn_with_packable_analyzer_single_phase(inputs):
      x, y = inputs["x"], inputs["y"]
      x_mean = tft.mean(x, name="x")
      x_centered = x - x_mean
      y_mean = tft.mean(y, name="y")
      y_centered = y - y_mean
      z = inputs["z"]
      z_vocab = tft.vocabulary(z, name="z")
      _ = tft.experimental.approximate_vocabulary(
          z, top_k=10, name="z_approx"
      )
      initializer = tf.lookup.TextFileInitializer(
          z_vocab,
          key_dtype=tf.string,
          key_index=tf.lookup.TextFileIndex.WHOLE_LINE,
          value_dtype=tf.int64,
          value_index=tf.lookup.TextFileIndex.LINE_NUMBER,
      )
      table = tf.lookup.StaticHashTable(initializer, default_value=-1)
      z_integerized = table.lookup(z)
      return {
          "x_centered": x_centered,
          "y_centered": y_centered,
          "z_integerized": z_integerized,
      }
  
file_path: transform/tensorflow_transform/beam/combiner_packing_util_test.py
imports: from unittest import mock
  import tensorflow
  import tensorflow_transform
  from tensorflow_transform import impl_helper
  from tensorflow_transform import nodes
  from tensorflow_transform.beam import analysis_graph_builder
  from tensorflow_transform.beam import combiner_packing_util
  from tensorflow_transform import test_case
label_desc: Use image node_id 1 for calling a global function with example usage: _preprocessing_fn_with_packable_analyzer_single_phase(inputs) and returns: dict