code: def main(args):
      
      examples = []
      with open(args.input, 'r') as fin:
          reader = csv.DictReader(fin, delimiter='\t')
          for cols in reader:
              s1 = read_tokens(cols['sentence1_parse'])
              s2 = read_tokens(cols['sentence2_parse'])
              label = cols['gold_label']
              if label in ('neutral', 'contradiction', 'entailment'):
                  examples.append((s1, s2, label))
      with open(args.output, 'w') as fout:
          for s1, s2, l in examples:
              fout.write('{}\t{}\t{}\n'.format(' '.join(s1), ' '.join(s2), l))
docs: Read tokens from the provided parse tree in the SNLI dataset.
      Illegal examples are removed.