old_contents: import pytest
  
  class TennisGame:
  	def score(self):
  		return (0,0) 
  #TESTS
  def test_empty_game():
  	game = TennisGame()
  	assert (game.score()[0] == 0 and game.score()[1] == 0) 
  
new_contents: import pytest
  
  class TennisGame:
  	PLAYER_ONE = 0
  	def add_point(self,player):
  		pass
  	def score(self):
  		return (0,0) 
  #TESTS
  def test_empty_game():
  	game = TennisGame()
  	assert (game.score()[0] == 0 and game.score()[1] == 0) 
  
  def test_first_player_makes_first_point():
  	game = TennisGame()
  	game.add_point(TennisGame.PLAYER_ONE)
  	assert (game.score()[0] == 15 and game.score()[1] == 0) 
  
subject: add second test to tennis kata