Table: anand_kramnik_games
Columns: white
black
year
result
moves
tournament
opening

Question: Who was the opponent of Anand in the match with 20 moves that opened with E15 Queen's Indian Defence?
SQL: SELECT "black" FROM anand_kramnik_games WHERE "white" = 'anand' AND "moves" = 20 AND "opening" = 'e15 queen''s indian defence'