This might be one of those "depends on your agreements" ones, but here goes anyway...
You deal and open 1♦ (showing 5 unless 4441 black singleton).
1♦ -- (1♥) -- 3♠* -- (4♥)
?
* GF fit jump, 2/4 or 3/5 top spade honours in a 5+ suit, at least 4 card diamond support.
2♠ would also have been a fit jump but could be more-lead oriented. 3♠ declares it's our hand and sets up a FP...
Which action do you choose?

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