@staticmethod
    def solution_to_string(puzzle_list):
        """
        return a solution as String

        puzzleList[0] = top left
        puzzleList[1] = top center
        ...(line by line)
        puzzleList[8] = bottom right

        saving in output first facility storage elsewhere later. If desired...
        """
        output = "+--------+--------+--------+\n"
        output += "|{0:5d}   |{1:5d}   |{2:5d}   |\n".format(puzzle_list[0].get_side_up(),
                                                             puzzle_list[1].get_side_up(),
                                                             puzzle_list[2].get_side_up())
        output += "|{0:2d}{1:3d}{2:3d}".format(puzzle_list[0].get_side_left(),
                                               puzzle_list[0].get_puzzle_type(),
                                               puzzle_list[0].get_side_right())
        output += "|{0:2d}{1:3d}{2:3d}".format(puzzle_list[1].get_side_left(),
                                               puzzle_list[1].get_puzzle_type(),
                                               puzzle_list[1].get_side_right())
        output += "|{0:2d}{1:3d}{2:3d}|\n".format(puzzle_list[2].get_side_left(),
                                                  puzzle_list[2].get_puzzle_type(),
                                                  puzzle_list[2].get_side_right())
        output += "|{0:5d}   |{1:5d}   |{2:5d}   |\n".format(puzzle_list[0].get_side_down(),
                                                             puzzle_list[1].get_side_down(),
                                                             puzzle_list[2].get_side_down())
        output += "+--------+--------+--------+\n"
        output += "|{0:5d}   |{1:5d}   |{2:5d}   |\n".format(puzzle_list[3].get_side_up(),
                                                             puzzle_list[4].get_side_up(),
                                                             puzzle_list[5].get_side_up())
        output += "|{0:2d}{1:3d}{2:3d}".format(puzzle_list[3].get_side_left(),
                                               puzzle_list[3].get_puzzle_type(),
                                               puzzle_list[3].get_side_right())
        output += "|{0:2d}{1:3d}{2:3d}".format(puzzle_list[4].get_side_left(),
                                               puzzle_list[4].get_puzzle_type(),
                                               puzzle_list[4].get_side_right())
        output += "|{0:2d}{1:3d}{2:3d}|\n".format(puzzle_list[5].get_side_left(),
                                                  puzzle_list[5].get_puzzle_type(),
                                                  puzzle_list[5].get_side_right())
        output += "|{0:5d}   |{1:5d}   |{2:5d}   |\n".format(puzzle_list[3].get_side_down(),
                                                             puzzle_list[4].get_side_down(),
                                                             puzzle_list[5].get_side_down())
        output += "+--------+--------+--------+\n"  #
        output += "|{0:5d}   |{1:5d}   |{2:5d}   |\n".format(puzzle_list[6].get_side_up(),
                                                             puzzle_list[7].get_side_up(),
                                                             puzzle_list[8].get_side_up())
        output += "|{0:2d}{1:3d}{2:3d}".format(puzzle_list[6].get_side_left(),
                                               puzzle_list[6].get_puzzle_type(),
                                               puzzle_list[6].get_side_right())
        output += "|{0:2d}{1:3d}{2:3d}".format(puzzle_list[7].get_side_left(),
                                               puzzle_list[7].get_puzzle_type(),
                                               puzzle_list[7].get_side_right())
        output += "|{0:2d}{1:3d}{2:3d}|\n".format(puzzle_list[8].get_side_left(),
                                                  puzzle_list[8].get_puzzle_type(),
                                                  puzzle_list[8].get_side_right())
        output += "|{0:5d}   |{1:5d}   |{2:5d}   |\n".format(puzzle_list[6].get_side_down(),
                                                             puzzle_list[7].get_side_down(),
                                                             puzzle_list[8].get_side_down())
        output += "+--------+--------+--------+\n"

        return output