Write SQL query to solve given problem: How many umpires are from South Africa?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT SUM(CASE WHEN T1.Country_Name = 'South Africa' THEN 1 ELSE 0 END) FROM Country AS T1 INNER JOIN Umpire AS T2 ON T1.Country_ID = T2.Umpire_Country