How many samples taken from producer Qingdao Suncare Nutritional Technology with a melamine content less than 53.4?
CREATE TABLE "tests_conducted_by_aqsiq" (
  "producer" text,
  "product" text,
  "samples_taken" real,
  "samples_failed" real,
  "melamine_content_mg_kg" real
);
SELECT SUM("samples_taken") FROM "tests_conducted_by_aqsiq" WHERE "melamine_content_mg_kg"<53.4 AND "producer"='qingdao suncare nutritional technology';