Database: formula_1
Question: How many times did Michael Schumacher won from races hosted in Sepang International Circuit?
SQL: SELECT SUM(T2.wins) FROM drivers AS T1 INNER JOIN driverStandings AS T2 ON T2.driverId = T1.driverId INNER JOIN races AS T3 ON T3.raceId = T2.raceId INNER JOIN circuits AS T4 ON T4.circuitId = T3.circuitId WHERE T1.forename = 'Michael' AND T1.surname = 'Schumacher' AND T4.name = 'Sepang International Circuit'