(a) Assessors of property for metropolitan governments shall assess separately and keep separate records and make up separate assessment rolls for:
(1) Property in the urban services district;
(2) Property within the limits of each incorporated city; and
(3) Other property, being all property in the general services district and not in the urban services district or in any incorporated city.
(b) The aggregate of the enumerated assessment records and rolls shall be the assessment records and rolls for the general services district, and the assessor of property shall so certify to the trustee, without obligation or a need to compile any other record or roll for the general services district.