about this carefullyyou will see that probability and score are properties related to particular playerswhile the server is property of the game between the two players that suggests that we might simply consider that game needs to know who the players are and which is serving the players themselves can be objects that know their probability and score thinking about the rballgame class this way leads us to design some new objects if the players are objectsthen we will need another class to define their behavior let' name that class player player object will keep track of its probability and current score when player is first created the probability will be supplied as parameterbut the score will just start out at we'll flesh out the design of player class methods as we work on rballgame we are now in position to define the constructor for rballgame the game will need instance variables for the two players and another variable to keep track of which player is serving class rballgamedef __init__(selfprobaprobb)self playera player(probaself playerb player(probbself server self playera player always serves first sometimes it helps to draw picture to see the relationships among the objects that we are creating suppose we create an instance of rballgame like thisthegame rballgame figure shows an abstract picture of the objects created by this statement and their interrelationships player rballgame playeraprob score playerbserverplayer prob score figure abstract view of rballgame object oknow that we can create an rballgamewe need to figure out how to play it going back to the discussion of racquetball from we need an algorithm that continues to serve rallies