What was the original airdate of the episode 'The Cold Turkey', which was viewed by 3.73 million viewers?
CREATE TABLE table_21731 (
    "Series #" real,
    "Episode #" real,
    "Title" text,
    "Directed by" text,
    "Written by" text,
    "U.S. viewers (million)" text,
    "Original airdate" text,
    "Production Code" text
)
SELECT "Original airdate" FROM table_21731 WHERE "U.S. viewers (million)" = '3.73'
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: What was the original airdate of the episode 'The Cold Turkey', which was viewed by 3.73 million viewers? ### Input: CREATE TABLE table_21731 (
    "Series #" real,
    "Episode #" real,
    "Title" text,
    "Directed by" text,
    "Written by" text,
    "U.S. viewers (million)" text,
    "Original airdate" text,
    "Production Code" text
) ### Response: SELECT "Original airdate" FROM table_21731 WHERE "U.S. viewers (million)" = '3.73'