code: def main(_):
      pipeline = calculate_metrics()
      pipeline.run().wait_until_finish()
  
file_path: text/tensorflow_text/tools/wordpiece_vocab/measure_wordpiece_stats.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import tempfile
  from absl import app
  from absl import flags
  import apache_beam
  import tensorflow.compat.v1
  import tensorflow_transform
  import tensorflow_transform.beam
  from tensorflow_transform.tf_metadata import dataset_metadata
  from tensorflow_transform.tf_metadata import schema_utils
  from tensorflow_text.tools.wordpiece_vocab import utils
label_desc: Use image node_id 2 for calling a global function with example usage: main(_) without return types