Which Sub-Parish (Sogn) is in the Parish (Prestegjeld) of hafslo parish and has a church called Hafslo Kyrkje?
CREATE TABLE "churches_in_luster" (
  "parish_prestegjeld" text,
  "sub_parish_sogn" text,
  "church_name" text,
  "year_built" real,
  "location_of_the_church" text
);
SELECT "sub_parish_sogn" FROM "churches_in_luster" WHERE "parish_prestegjeld"='hafslo parish' AND "church_name"='hafslo kyrkje';