user: Question: Name who wrote the episode that aired April 9, 1989
Columns: ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'text']
Sample row: [36.0, 1.0, '"He Thought He Could"', 'Gerry Cohen', 'Ron Leavitt & Michael G. Moye', 'November 6, 1988', '3.01']
SQL:

assistant: SELECT "Written by" FROM "Table" WHERE "Original air date" = 'April 9, 1989';