When was the duchess, who was married on 11 july 1643, born?
CREATE TABLE "house_of_savoy" (
  "name" text,
  "father" text,
  "birth" text,
  "marriage" text,
  "became_duchess" text,
  "ceased_to_be_duchess" text,
  "death" text,
  "spouse" text
);
SELECT "birth" FROM "house_of_savoy" WHERE "marriage"='11 july 1643';