Every operator of such circus, carnival, amusement center or go-kart center shall obtain and maintain in full force and effect public liability insurance in the sum of two hundred fifty thousand dollars for death or injury to one person, and five hundred thousand dollars for the death or injury to more than one person in the same accident or occurrence. Said operator will file with the city clerk a certificate of insurance in the amounts herein indicated showing the city of Everett as a named insured on such policy. (Ord. 518-78 § 6, 1978.)