Section 11. Other receipts taxes.
Notwithstanding anything contained in any law to the contrary, and except when specifically authorized by the General Assembly, no city council of a city of the first class may levy, assess or collect, for city purposes, any tax, based on or measured by gross receipts, for the privilege of doing business in the city if the city already provides for the imposition, levy and collection of the tax imposed and authorized by this act.