What is the average of the Series #s that were directed by Matthew Penn?
CREATE TABLE table_name_42 (
    series__number INTEGER,
    directed_by VARCHAR
)
SELECT AVG(series__number) FROM table_name_42 WHERE directed_by = "matthew penn"
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 is the average of the Series #s that were directed by Matthew Penn? ### Input: CREATE TABLE table_name_42 (
    series__number INTEGER,
    directed_by VARCHAR
) ### Response: SELECT AVG(series__number) FROM table_name_42 WHERE directed_by = "matthew penn"