SELECT "Written by" FROM table_3500 WHERE "No." = '38'
Who wrote title number 38?
CREATE TABLE table_3500 (
    "No." real,
    "#" real,
    "Title" text,
    "Directed by" text,
    "Written by" text,
    "U.S. viewers (million)" text,
    "Rank (week)" text,
    "Original air date" text,
    "Production code" text
)