user: Question: What was the year of the finish with the class pos of 6th and laps smaller than 317?
Columns: ['Year', 'Team', 'Co-Drivers', 'Class', 'Laps', 'Pos.', 'Class Pos.']
Types: ['real', 'text', 'text', 'text', 'real', 'text', 'text']
Sample row: [1997.0, 'GT1 Lotus Racing', 'Jan Lammers Alexander Grau', 'GT1', 121.0, 'DNF', 'DNF']
SQL:

assistant: SELECT "Year" FROM "Table" WHERE "Class Pos." = '6th' AND "Laps" < 317.0;