user: ### NOW ANSWER:
Question: Which year was the vessel Deva built as a Panamax DNV class ship?
Columns: ['Vessel Name', 'Type', 'Built', 'Class', 'Flag']
Types: ['text', 'text', 'real', 'text', 'text']
Sample row: ['Hyundai Advance', 'Panamax', 1997.0, 'KR', 'Panama']
SQL:

assistant: SELECT SUM("Built") FROM "Table" WHERE "Class" = 'DNV' AND "Type" = 'Panamax' AND "Vessel Name" = 'Deva';