class_docstr: Paraphrase problem.
code: def prepare_data(self, data_dir, tmp_dir, dataset_split):
      ms_coco_path = self._maybe_download(tmp_dir, dataset_split)
      captions = self._get_captions(ms_coco_path)
      tf.logging.info("Retrieved %d captions\n" % (len(captions)))
      paraphrase_pairs = []
  
      tf.logging.info("Generating input combinations...")
      for captions_for_image in captions:
          combinations_of_captions = create_combination(
              captions_for_image
          )
          paraphrase_pairs += combinations_of_captions
  
      tf.logging.info(
          "Created %d combinations pairs." % (len(paraphrase_pairs))
      )
      return paraphrase_pairs
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  import io
  import json
  import os
  import zipfile
  from tensor2tensor.data_generators import generator_utils
  from tensor2tensor.data_generators import problem
  from tensor2tensor.data_generators import text_problems
  from tensor2tensor.utils import registry
  import tensorflow.compat.v1
label_desc: Use image node_id 4 for calling the ParaphraseGenerationMsCocoProblem obj's underlying member method code with example usage: obj.prepare_data(data_dir, tmp_dir, dataset_split) and returns: paraphrase_pairs