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_21666472_1 (no_in_series VARCHAR, written_by VARCHAR)
### Question:
How many number in series's are written by Greg Haddrick?
### Answer:
SELECT COUNT(no_in_series) FROM table_21666472_1 WHERE written_by = "Greg Haddrick"