In any county in which a city of the metropolitan class is located, there is hereby created the office of county comptroller for such county, and the county clerk of such county shall be the ex officio county comptroller for the county. The county comptroller shall act as the general accountant and fiscal agent of the county and shall exercise a general supervision over all officers of the county charged in any manner with the receipt, collection, or disbursement of the county revenue. The county comptroller shall be a competent bookkeeper and accountant, and it shall be his or her duty to keep a complete set of books in which, among other things, the amount of the appropriation that has been made on the fund that has been expended on account of such appropriation fund shall be stated. It shall be the duty of the county comptroller to audit all claims filed against the county and prepare a report thereon to the county board of such county. The county comptroller shall also keep accurate and separate accounts between the county and officers of the county, and between the county and all contractors or other persons doing work or furnishing material for the county. The county comptroller shall also examine and check the reports of all officers of the county. The county comptroller shall prepare and file the required annual inventory statement of county personal property in his or her custody or possession, as provided in sections 23-346 to 23-350.