code: def _answer_to_bags(self, answer):
      if isinstance(answer, (list, tuple)):
          raw_spans = answer
      else:
          raw_spans = [answer]
      normalized_spans = []
      token_bags = []
      for raw_span in raw_spans:
          normalized_span = self._normalize(raw_span)
          normalized_spans.append(normalized_span)
          token_bags.append(set(normalized_span.split()))
      return normalized_spans, token_bags
  
imports: import inspect
  import numpy
  import re
  import string
  import lm_eval.datasets.drop.drop
  from scipy.optimize import linear_sum_assignment
  from lm_eval.base import Task, rf
  from lm_eval.metrics import mean
label_desc: Use image node_id 16 for calling the DROP obj's underlying member method code with example usage: obj._answer_to_bags(answer) and returns: normalized_spans,  token_bags