We start with the question of the South hand. Is it an opening 1♠, 2♠ (or 2♦ multi), or is it a pass? Let's take each of these cases separately.
If south opens 1♠, North has a bit of a problem playing 2/1 as GF. I think many would bid an invitational jump shift of 3♣ as it is going to be impossible to get across your 7/4 shape. Those that can start with a natural 2♣ here have a relatively easy pass of 2♠.
If south opens 2♠, North will pass and hope that hearts have been preempted (and they have).
If south passes, it goes over to North. North has a shapely hand, but I for one, would be worried about having only two cards in the majors. I'm probably a lone voice here, but I would open a preemptive 3♣ on the north hand. Note that 3rd seat openings do not deny open values, they just do not think game is possible opposite a passed partner. However, most Norths will open a natural 1♣ in 3rd. Then the preemption begins as only if it goes P - P - 1♣ will East enter with 1♥. South has an easy 1♠ over this, but West puts the maximum pressure on with 4♥. What can North do now? Most will begrudgingly bid 4♠ and the damage has been done.

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