user: Question: Name the total number of episodes written by David Cantor
Columns: ['Episode', 'Original title', 'Directed by', 'Written by', 'Original airdate', 'Duration', 'Viewership']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [16.0, '" But is it Art? "', 'Dewi Humphreys', 'Jim Sullivan', '2November2007', '30 minutes', '5.34 million']
SQL:

assistant: SELECT COUNT("Episode") FROM "Table" WHERE "Written by" = 'David Cantor';