Prisoners dilemma algorithm-random player

I have a homework to make an algorithm of player, which will play a tournament, based on prisoners dilemma. Each game will have random iretations. I I want to treat option, if my opponent in tournament will choose answer randomly.Every iteration, I can save opponent move in array(True=Defect, False=Cooperate). Does it exist some solution of my problem? I would be grateful, if you can help me.