user: Question: What is the average number of borough councilors from Brompton?
Columns: ['Borough', 'Components', 'Population', 'Number of Borough Councilors', 'Number of Municipal Councilors']
Types: ['text', 'text', 'real', 'real', 'real']
Sample row: ['Brompton', 'Bromptonville', 5771.0, 3.0, 1.0]
SQL:

assistant: SELECT AVG("Number of Borough Councilors") FROM "Table" WHERE "Borough" = 'Brompton';