user: Question: What is the channel number that has a branding of PTV 4 Laoag?
Columns: ['Branding', 'Callsign', 'Ch. #', 'Power kW', 'Station Type', 'Location (Transmitter site)']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['PTV 4 Manila', 'DWGT-TV', 'TV-4', '50 kW (500 kW ERP)', 'Originating', 'Metro Manila']
SQL:

assistant: SELECT "Ch. #" FROM "Table" WHERE "Branding" = 'PTV 4 Laoag';