class_docstr: Base class for transferring styles problems
class_docstr_tok: ["Base","class","for","transferring","styles","problems"]
docstr: Files to be passed to get_or_generate_vocab.
docstr_tok: ["Files","to","be","passed","to","get_or_generate_vocab","."]
code: def vocab_data_files(self):
      """Files to be passed to get_or_generate_vocab."""
      return self.dataset_url(problem.DatasetSplit.TRAIN)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  import tarfile
  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
label_desc: Use image node_id 4 for calling the StyleTransferProblemShakespeare obj's underlying member method code with example usage: obj.vocab_data_files() and returns: self