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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def random_start_board(cls):
 """Produce a full, stable start board with random tiles."""

        board = cls()
        board._random_fill()
        destructions = True  # prime the loop
        while destructions:
            board, destructions = board.execute_once()
            board._random_fill()
        return board