new_contents: from __future__ import absolute_import
  
  from future import str_is_unicode
  
  import unittest
  
  class TestIterators(unittest.TestCase):
      def test_str(self):
          self.assertIsNot(str, bytes)            # Py2: assertIsNot only in 2.7
          self.assertEqual(str('blah'), u'blah')  # Py3.3 and Py2 only
  
  unittest.main()
  
subject: Add tests for str_is_unicode module