user: Question: How many original air dates were there for episodes with a production code of 4398016?
Columns: ['No in Series', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code', 'U.S. viewers (millions)']
Types: ['real', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: [1.0, '" Something Wicca This Way Comes "', 'John T. Kretchmer', 'Constance M. Burge', 'October7,1998', 1498704.0, '7.7']
SQL:

assistant: SELECT COUNT("Original air date") FROM "Table" WHERE "Production code" = 4398016.0;