 Country A should specialize in the production of wheat and export it as trade for wine from Country B.
 Country B should specialize in wine production and export it as trade for wheat from Country A.

 Country A should specialize in the production of wheat and export it as trade for wine from Country B.
 Country B should specialize in wine production and export it as trade for wheat from Country A.

 Country A should specialize in the production of wheat and export it as trade for wine from Country B.
 Country B should specialize in wine production and export it as trade for wheat from Country A.

 Country A should specialize in the production of wheat and export it as trade for wine from Country B.
 Country B should specialize in wine production and export it as trade for wheat from Country A.

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