If an order of exclusion is granted, the board and the governing body of the city shall by contract provide for the payment by the city of the proportion of the taxes and bonded indebtedness for which the territory excluded is justly liable. If they do not agree, either may petition the superior court in and for the county in which the property is located for a judgment declaring the proportion of the taxes and bonded indebtedness for which the territory excluded is justly liable. The proceeding shall be governed by the provisions of the Code of Civil Procedure relating to declaratory relief.