user: Question: Callsign of 6NAN has what purpose?
Columns: ['Callsign', 'Area served', 'Frequency', 'Band', 'On-air ID', 'Purpose']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['6AAY', 'Albany', '0 95.3', 'FM', 'Hot FM', 'Commercial']
SQL:

assistant: SELECT "Purpose" FROM "Table" WHERE "Callsign" = '6NAN';