2. In the original prisoners' dilemma game, with payoffs as in Figure 5.1, when one prisoner con- fesses and 'grasses' on his accomplice, the 'grass' gets off with no jail sentence at all. Consider the case where both partners in crime make it clear to each other that if they grass and go free, they will subsequently be visited and punished by a friend of the jailed felon. Suppose the punishment counts as equivalent to a 2-year stretch in jail. Find the Nash equilibria for this new game.