user: Question: What year at the US Open Cup Quarterfinals, were the playoffs in the Semifinals for the USL Second Division?
Columns: ['Year', 'Division', 'League', 'Regular Season', 'Playoffs', 'U.S. Open Cup', 'Avg. Attendance']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'real']
Sample row: [2004.0, 3.0, 'USL Pro Soccer League', '2nd, Atlantic', 'Quarterfinals', 'Did not qualify', 1510.0]
SQL:

assistant: SELECT "Year" FROM "Table" WHERE "League" = 'USL Second Division' AND "Playoffs" = 'Semifinals' AND "U.S. Open Cup" = 'Quarterfinals';