user: Question: Name the total number of weeks for si te vas and peak less than 7 and year less than 2000
Columns: ['Year', 'Chart', 'Track', 'Peak', 'Weeks on Chart']
Types: ['real', 'text', 'text', 'real', 'real']
Sample row: [2000.0, 'Billboard Hot Latin Songs', 'Quiéreme', 3.0, 20.0]
SQL:

assistant: SELECT SUM("Weeks on Chart") FROM "Table" WHERE "Track" = 'si te vas' AND "Peak" < 7.0 AND "Year" < 2000.0;