There shall be a sinking fund commission consisting of the mayor, the director of finance, and the director of law. The mayor shall be the president and the director of finance the secretary of the commission. Under such regulations as may be established by ordinance, and in conformity with any law of the state applicable to the city and providing for or fixing the duties of a sinking fund commission, it shall be the duty of such commission to have charge of the administration of any fund for the payment of the principal and interest of any bonds of the city and to perform such other duties regarding the debt of the city as may be required by ordinance.