(a)   Every officer, whether elected or appointed, shall, upon entering upon the duties of his or her office, take and subscribe an oath or affirmation, which may be in the following form:
      I do solemnly swear that I will support the Constitution of the United States and the Constitution of the State of Illinois and will faithfully discharge the duties of the office of ___________________________ of the City of Christopher, Illinois, according to the best of my ability.
   (b)   The oath of office shall, in all cases, be administered by the City Clerk, except his or her oath which shall be administered by the Mayor. Such oaths of office shall be in writing and shall be filed in the office of the City Clerk, except the oath of the Clerk, which shall be filed with the City Treasurer.