user: Question: How many episodes were directed by Arlene Sanford?
Columns: ['No. in series', 'No. in 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: [16.0, 1.0, '" American Duos "', 'John Landis', 'Steve Franks & James Roday', 'July13,2007', 2002.0, '4.33']
SQL:

assistant: SELECT COUNT("Written by") FROM "Table" WHERE "Directed by" = 'Arlene Sanford';