(a) An action or proceeding may be prosecuted or defended by a party in person or by attorney. However,
(1) the United States shall appear by an attorney in all cases; and
(2) a corporation, either public or private, shall appear by an attorney in all cases unless an exception to the corporation's appearance by an attorney has been explicitly made by law.
(b) When a party appears by attorney, the written proceedings shall be in the name of the attorney, who is the sole representative of the client as between the client and the adverse party.