old_contents: from scores import ScoreService
  from nameko.testing.services import worker_factory
  
  
  class TestScores(unittest.TestCase):
      def test_leaderboard(self):
          service = worker_factory(ScoreService)
          service.player_rpc.new_player('player1')
          service.player_rpc.new_player('player2')
          service.player_rpc.get_player(1).add_score(10)
          service.player_rpc.get_player(2).add_score(20)
  
          self.assertEquals(
              service.leaderboard(),
              [('player2', 20), ('player1', 10)])
  
      def test_empty_leaderboard(self):
          service = worker_factory(ScoreService)
          self.assertEquals(service.leaderboard(), [])
  
new_contents: from scores import ScoreService
  from nameko.testing.services import worker_factory
  
  
  def test_leaderboard(self):
      service = worker_factory(ScoreService)
      service.player_rpc.new_player('player1')
      service.player_rpc.new_player('player2')
      service.player_rpc.get_player(1).add_score(10)
      service.player_rpc.get_player(2).add_score(20)
  
      self.assertEquals(
          service.leaderboard(),
          [('player2', 20), ('player1', 10)])
  
  def test_empty_leaderboard(self):
      service = worker_factory(ScoreService)
      self.assertEquals(service.leaderboard(), [])
  
subject: Remove old unittest class