class_docstr: Transforms an input by adding summaries of person and movies provided
  by csv.
  
  Example::
  
      ori: Titanic is my favorite movie.
      trans: Titanic(A seventeen-year-old aristocrat falls in love with a
      kind but poor artist aboard the
             luxurious,ill-fated R.M.S. Titanic.) is my favorite movie.
docstr: Transform text string, this kind of transformation can only produce
  one sample.
  
  :param ~SASample sample: input data, a SASample contains 'x' field and
      'y' field
  :param int n: number of generated samples, this transformation can only
      generate one sample
  :return list trans_samples: transformed sample list that only contain
      one sample
code: def _transform(self, sample, n=1, **kwargs):
      r"""
      Transform text string, this kind of transformation can only produce
      one sample.
  
      :param ~SASample sample: input data, a SASample contains 'x' field and
          'y' field
      :param int n: number of generated samples, this transformation can only
          generate one sample
      :return list trans_samples: transformed sample list that only contain
          one sample
  
      """
      # To speed up the query, dividing the original sentence into n-tuple
      # string
      tup_list = sample.concat_token(self.max_entity_len)
      insert_indices, insert_summaries = self._get_insert_info(tup_list)
      if not insert_indices:
          return []
  
      for insert_index, summary in zip(
          insert_indices, insert_summaries
      ):
          summary_tokens = self.processor.tokenize(summary)
          sample = sample.insert_field_after_index(
              "x", insert_index, summary_tokens
          )
      trans_samples = [sample]
      return trans_samples
  
file_path: textflint/textflint/generation/transformation/SA/add_sum.py
imports: from ..transformation import Transformation
  from ....common.settings import SA_PERSON_PATH, SA_MOVIE_PATH
  from ....common.utils.install import download_if_needed
  from ....common.utils.load import sa_dict_loader
label_desc: Use image node_id 3 for calling the AddSum obj's underlying member method code with example usage: obj._transform(sample, n) and returns: trans_samples, list