SECTION 4.05 APPROPRIATION AND REVENUE ORDINANCES.
   To implement the adopted budget of the ensuing fiscal year, the City Council:
   a.   Shall, no later than its first regular meeting in September of each year or within 10 days thereafter, introduce the annual appropriation ordinance for the ensuing fiscal year, in which it shall appropriate the sums of money necessary to meet all lawful expenses and liabilities of the municipality. The ordinance shall specify the function and subfunction as prescribed by the department of legislative audit for which the appropriations are made and the amount appropriated for each function and subfunction, which amount shall be appropriated from the proper fund. It is not necessary to appropriate revenue to be expended from an enterprise or trust and agency fund if the fund is not supported or subsidized by revenue derived from the annual appropriated tax levy. However, an annual budget for these funds shall be developed and published no later than the last day of December of each year.
   b.   Shall adopt any other ordinances required to authorize new revenues or to amend the rates or other features of existing taxes or other revenue sources.