Except as otherwise provided by this part, all laws and parts of laws, general, local, or special, relating to or affecting the city, its powers, functions, duties, and property, in force on September 9, 1955, are hereby continued in effect; but all such laws relating to the exercise of powers, functions, and duties by the commission or council-manager or some other form of government shall be superseded to the extent that the same are inconsistent with this part.