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Play Problem 018
Someone asked the question whether it was theoretically possible for both sides to bid and make 7NT.
Here's one suggestion

7 NT played by South
7 NT played by West

If South is declarer in 7 NT, the lead comes from West who has only clubs and a spade.  So South can't fail to take all 13 tricks in hand.

If West is declarer in 7NT, the lead would come from North who only has hearts and a diamond.  So West takes all 13 tricks in dummy.