new_contents: # This is an example unit test suite for creating an AI
  from game import GameRunner, Board, Player
  from demo import BattleshipsAI
  from unittest import TestCase
  
  class TestPlayer(Player):
      """ Mock Player which records ships placed and shots taken """
      def __init__(self):
          super(TestPlayer, self).__init__()
          self.placed_ships = []
          self.shots_taken = 0
  
      def place_ship(self, size, x, y, direction):
          self.placed_ships.append(size)
          super(TestPlayer, self).place_ship(size, x, y, direction)
  
      def take_shot(self, x, y):
          self.shots_taken += 1
  
  
  class TestBattleshipsAI(TestCase):
      def setUp(self):
          self.ai = BattleshipsAI()
  
      def test_places_all_ships(self):
          """ Test that all ships are placed. """
          player = TestPlayer()
          self.ai.place_ships(player)
          sorted_ships = sorted(player.placed_ships)
          self.assertEqual([2, 3, 3, 4, 5], sorted_ships)
  
      def test_takes_shot(self):
          """ Test that the AI takes a shot. """
          player = TestPlayer()
          self.ai.take_shot(player)
          self.assertEqual(1, player.shots_taken)
  
subject: Add very simple demo unit tests