new_contents: 
  from openrcv.formats.internal import to_internal_ballot
  from openrcv.utiltest.helpers import UnitCase
  
  
  class InternalModuleTest(UnitCase):
  
      def test_to_internal_ballot(self):
          cases = [
              ((1, (2, )), "1 2"),
              ((1, (2, 3)), "1 2 3"),
              ((1, ()), "1"),
          ]
          for ballot, expected in cases:
              with self.subTest(ballot=ballot, expected=expected):
                  self.assertEqual(to_internal_ballot(ballot), expected)
  
subject: Add test_internal.py.