what is the nation when the world rank is 2 and the birth date is 1976-12-20?
CREATE TABLE "sortable_list_of_competitors_with_s_kipp" (
  "nation" text,
  "birth_date" text,
  "height_m" text,
  "weight_kg" text,
  "world_rank" text
);
SELECT "nation" FROM "sortable_list_of_competitors_with_s_kipp" WHERE "world_rank"='2' AND "birth_date"='1976-12-20';