user: Question: Who wrote the episode directed by Ken Whittingham?
Columns: ['Series #', 'Season #', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code', 'U.S. viewers (millions)']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: [151.0, 1.0, '" My Jerks "', 'Michael Spiller', 'Angela Nissel', 'January6,2009', 801.0, '6.76']
SQL:

assistant: SELECT "Written by" FROM "Table" WHERE "Directed by" = 'Ken Whittingham';