user: Question: Which masters fought in Hapkido style?
Columns: ['Episode #', 'Country', 'City', 'Martial Art/Style', 'Masters', 'Original Airdate']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['1.1', 'China', 'Dengfeng', 'Kung Fu ( Wushu ; Sanda )', 'Shi De Yang, Shi De Cheng', 'December 28, 2007']
SQL:

assistant: SELECT "Masters" FROM "Table" WHERE "Martial Art/Style" = 'Hapkido';