code: def test_f_score_2():
      sentences = (("s1", "s3", "s6"), ("s1", "s2", "s3", "s4", "s5"))
      result = f_score(*sentences, weight=0.5)
  
      p = 2 / 3
      r = 2 / 5
      # ( (W^2 + 1) * P * R ) / ( W^2 * P + R )
      expected = (1.25 * p * r) / (0.25 * p + r)
  
      assert result == approx(expected)
  
imports: from __future__ import absolute_import
  from __future__ import division, print_function, unicode_literals
  import pytest
  from pytest import approx
  from sumy.evaluation import precision, recall, f_score
label_desc: Use image node_id 20 for calling a global function with example usage: test_f_score_2() without return types