user: Question: When Butler one the regular season who was the conference player of the year?
Columns: ['Conference', 'Regular Season Winner', 'Conference Player of the Year', 'Conference Tournament', 'Tournament Venue (City)', 'Tournament Winner']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Atlantic 10 Conference', "Temple & St. Joseph's (East) Xavier (West)", 'David West , Xavier', "2002 Atlantic 10 Men's Basketball Tournament", 'The Spectrum ( Philadelphia , Pennsylvania)', 'Xavier']
SQL:

assistant: SELECT "Conference Player of the Year" FROM "Table" WHERE "Regular Season Winner" = 'Butler';