user: Question: How many tons was the ship from norway?
Columns: ['Date', 'Ship', 'Tons', 'Nationality', 'Fate and location']
Types: ['text', 'text', 'real', 'text', 'text']
Sample row: ['22 January 1942', 'Vassilios A. Polemis', 3429.0, 'Greece', 'Sunk at']
SQL:

assistant: SELECT "Tons" FROM "Table" WHERE "Nationality" = 'norway';