user: Question: What districts does incumbent Curt Weldon hold?
Columns: ['District', 'Incumbent', 'Party', 'Elected', 'Status', 'Opponent']
Types: ['text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['Pennsylvania2', 'William H. Gray', 'Democratic', 1978.0, 'Re-elected', 'William H. Gray (D) 92.1% Donald Bakove (R) 7.9%']
SQL:

assistant: SELECT "District" FROM "Table" WHERE "Incumbent" = 'Curt Weldon';