How many million U.S. viewers was written by Matt Pelfrey?
CREATE TABLE table_31186 (
    "No." real,
    "Title" text,
    "Directed by" text,
    "Written by" text,
    "Featured character(s)" text,
    "U.S. viewers (millions)" text,
    "Original air date" text
)
SELECT "U.S. viewers (millions)" FROM table_31186 WHERE "Written by" = 'Matt Pelfrey'
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: How many million U.S. viewers was written by Matt Pelfrey? ### Input: CREATE TABLE table_31186 (
    "No." real,
    "Title" text,
    "Directed by" text,
    "Written by" text,
    "Featured character(s)" text,
    "U.S. viewers (millions)" text,
    "Original air date" text
) ### Response: SELECT "U.S. viewers (millions)" FROM table_31186 WHERE "Written by" = 'Matt Pelfrey'