Ordinance amending the Police Code to prohibit any person other than a licensed manufacturer or importer from possessing, selling, offering for sale, transferring, purchasing, transporting, receiving, or manufacturing an unfinished firearm frame or receiver that has not been imprinted with a serial number, subject to certain exceptions; and prohibiting any person from manufacturing or assembling a firearm that has not been imprinted with a serial number, subject to certain exceptions.