setup
    Board.__init__
    Location.__init__
    Board.is_legal_move
    Bear.__init__
    play
        print_state
            Location.__init__
        Board.get_closest_food
            Board.get_all_food_locs
                Location.__init__
            Location.distance
        Location.is_adjacent
            Location.distance
        Bear.eat_food
        Bear.move_towards_food
            Location.is_adjacent
                Location.distance
            Bear.move_one_square
                Location.__init__
                Board.is_legal_move