South plays 6♥. The auction was 6♥-P-P-P. 6♥ showed this exact hand. It does not come up that often, but boy was it nice here.
The lead is a diamond.
You are so excited about your 6♥ convention finally coming up, and hitting pay dirt, that you yell out, "I claim! Making!" You then have a sinking feeling.
You do not care about overtricks, because this is IMPs. However, down one would be devastating. So, can you back up your claim and state a line where 6♥ cannot possibly fail?

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You do not care about overtricks, because this is IMPs. However, down one would be devastating. So, can you back up your claim and state a line where 6♥ cannot possibly fail?