class_docstr: Scenario for single document text summarization.
  Currently supports the following datasets:
  1. XSum (https://arxiv.org/pdf/1808.08745.pdf)
  2. CNN/DailyMail non-anonymized (https://arxiv.org/pdf/1704.04368.pdf)
  
  Task prompt structure
  
      Summarize the given document.
      Document: {tok_1 ... tok_n}
      Summary: {tok_1 ... tok_m}
  
  Example from XSum dataset
  
      Document: {Part of the Broad Road was closed to traffic on Sunday at about 18:00 GMT.
                 The three adults and three children have been taken to Altnagelvin Hospital
                 with non life-threatening injuries. The Fire Service, Northern Ireland Ambulance Service
                 and police attended the crash. The Broad Road has since been reopened.}
      Summary: {Three adults and three children have been taken to hospital following a crash involving
                a tractor and a campervan in Limavady, County Londonderry}
class_docstr_tok: ["Scenario","for","single","document","text","summarization",".","Currently","supports","the","following","datasets",":","1",".","XSum","(","https",":","\/\/arxiv.org\/pdf\/1808.08745.pdf",")","2",".","CNN\/DailyMail","non-anonymized","(","https",":","\/\/arxiv.org\/pdf\/1704.04368.pdf",")","Task","prompt","structure","Summarize","the","given","document",".","Document",":","{","tok_1","...","tok_n","}","Summary",":","{","tok_1","...","tok_m","}","Example","from","XSum","dataset","Document",":","{","Part","of","the","Broad","Road","was","closed","to","traffic","on","Sunday","at","about","18:00","GMT",".","The","three","adults","and","three","children","have","been","taken","to","Altnagelvin","Hospital","with","non","life-threatening","injuries",".","The","Fire","Service",",","Northern","Ireland","Ambulance","Service","and","police","attended","the","crash",".","The","Broad","Road","has","since","been","reopened",".","}","Summary",":","{","Three","adults","and","three","children","have","been","taken","to","hospital","following","a","crash","involving","a","tractor","and","a","campervan","in","Limavady",",","County","Londonderry","}"]
code: def _load_dataset(self, dataset_name: str):
      if dataset_name == "xsum":
          url = "https://worksheets.codalab.org/rest/bundles/0xac5607f21bf945939edc56ea945496d5/contents/blob/"
          dataset = self._download_dataset(url, "xsum")
          article_key = "document"
          summary_key = "summary"
      elif dataset_name == "xsum-sampled":
          url = "https://worksheets.codalab.org/rest/bundles/0xcfbb0ef1226040f78e58060c9e4d13cf/contents/blob/"
          dataset = self._download_dataset(url, "xsum-sampled")
          article_key = "document"
          summary_key = "summary"
      elif dataset_name == "cnn-dm":
          url = "https://worksheets.codalab.org/rest/bundles/0x07630390bbda44879a2ad36e2125d64c/contents/blob/"
          dataset = self._download_dataset(url, "cnndm")
          article_key = "article"
          summary_key = "highlights"
      else:
          raise ValueError("The specified dataset is not supported")
  
      return dataset, article_key, summary_key
  
file_path: H2O/h2o_hf/helm/src/helm/benchmark/scenarios/summarization_scenario.py
imports: import os
  import pickle
  from typing import List, Optional
  from helm.common.general import ensure_file_downloaded, ensure_directory_exists
  from .scenario import Scenario, Instance, Reference, TRAIN_SPLIT, VALID_SPLIT, TEST_SPLIT, CORRECT_TAG, Input, Output
label_desc: Use image node_id 5 for calling the SummarizationScenario obj's underlying member method code with example usage: obj._load_dataset(dataset_name) and returns: dataset,  article_key,  summary_key