def test_equals_2(self):
     self.assertEqual(permutation_average(25), 39)
 def test_equals_4(self):
     self.assertEqual(permutation_average(737), 629)
 def test_equals(self):
     self.assertEqual(permutation_average(2), 2)
 def test_equals_3(self):
     self.assertEqual(permutation_average(20), 11)