user: Question: What Call sign has a City of license of Higgston, GA?
Columns: ['Call sign', 'Frequency MHz', 'City of license', 'ERP W', 'Class', 'FCC info']
Types: ['text', 'real', 'text', 'text', 'text', 'text']
Sample row: ['WKTM', 106.1, 'Soperton, GA', '6,000', 'A', 'FCC']
SQL:

assistant: SELECT "Call sign" FROM "Table" WHERE "City of license" = 'Higgston, GA';