how many million u.s. viewers watched the episode directed by dan lerner?
CREATE TABLE "table1_25997153_1" (
  "no_in_series" real,
  "no_in_season" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "original_air_date" text,
  "production_code" text,
  "u_s_viewers_million" text
);
SELECT "u_s_viewers_million" FROM "table1_25997153_1" WHERE "directed_by"='Dan Lerner';