What was the original air date for the episode with production code 1wab06?
CREATE TABLE "table1_20726262_2" (
  "no_in_series" real,
  "title" text,
  "directedby" text,
  "writtenby" text,
  "originalairdate" text,
  "production_code" text
);
SELECT "originalairdate" FROM "table1_20726262_2" WHERE "production_code"='1WAB06';