code: def rouge_2(hypotheses, references):
      """
      Calculate ROUGE-2 F1, precision, recall scores
      """
      rouge_2 = [
          rouge_n([hyp], [ref], 2)
          for hyp, ref in zip(hypotheses, references)
      ]
      rouge_2_f, _, _ = map(np.mean, zip(*rouge_2))
      return rouge_2_f
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from __future__ import unicode_literals
  import itertools
  import numpy
label_desc: Use image node_id 14 for calling a global function with example usage: rouge_2(hypotheses, references) and returns: rouge_2_f