How many episodes did Julie Martin wrote for the show If every episode has its own production code?
CREATE TABLE table_17623902_1 (
    production_code VARCHAR,
    written_by VARCHAR
)
SELECT COUNT(production_code) FROM table_17623902_1 WHERE written_by = "Julie Martin"
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 episodes did Julie Martin wrote for the show If every episode has its own production code? ### Input: CREATE TABLE table_17623902_1 (
    production_code VARCHAR,
    written_by VARCHAR
) ### Response: SELECT COUNT(production_code) FROM table_17623902_1 WHERE written_by = "Julie Martin"