user: ### NOW ANSWER:
Question: What are the nationalities of players who attended Duke?
Columns: ['Player', 'No.', 'Nationality', 'Position', 'Years for Grizzlies', 'School/Club Team']
Types: ['text', 'real', 'text', 'text', 'text', 'text']
Sample row: ['Bobby Jackson', 24.0, 'United States', 'Guard', '2005-2006', 'Minnesota']
SQL:

assistant: SELECT COUNT("Nationality") FROM "Table" WHERE "School/Club Team" = 'Duke';