Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_25851971_1 (production_code VARCHAR, written_by VARCHAR)
### Question:
What was the production code of the episode written by Anthony Sparks?
### Answer:
SELECT production_code FROM table_25851971_1 WHERE written_by = "Anthony Sparks"