user: Question: Name the sum of Laps for co-drivers of oliver gavin jan magnussen and class of gts with year less than 2004
Columns: ['Year', 'Team', 'Co-Drivers', 'Class', 'Laps', 'Pos.', 'Class Pos.']
Types: ['real', 'text', 'text', 'text', 'real', 'text', 'text']
Sample row: [1996.0, 'Viper Team Oreca', 'Philippe Gache Eric Hélary', 'GT1', 283.0, '21st', '12th']
SQL:

assistant: SELECT SUM("Laps") FROM "Table" WHERE "Co-Drivers" = 'oliver gavin jan magnussen' AND "Class" = 'gts' AND "Year" < 2004.0;