In all cities of the first class, the council may award, enter into, and let contracts for lighting the city streets, parks, and other public places, or either or any of the same, for any term not exceeding two years under any one contract. It shall not be necessary, before awarding or entering into such contracts, that provision by budget appropriations or otherwise shall first have been made to meet the indebtedness incurred by these contracts, but provision for meeting the obligation or indebtedness may be made after the letting of the contracts.