Who is the writer of episode 13?
CREATE TABLE table_2226817_8 (written_by VARCHAR, no_in_season VARCHAR)
SELECT COUNT(written_by) FROM table_2226817_8 WHERE no_in_season = 13
### Context: CREATE TABLE table_2226817_8 (written_by VARCHAR, no_in_season VARCHAR) ### Question: Who is the writer of episode 13? ### Answer: SELECT COUNT(written_by) FROM table_2226817_8 WHERE no_in_season = 13