Usurpation of authority or official functions. Any person who shall knowingly and falsely represent himself to be an officer, agent or representative of any department or agency of the Philippine Government or of any foreign government, or who, under pretense of official position, shall perform any act pertaining to any person in authority or public officer of the Philippine Government or of any foreign government, or any agency thereof, without being lawfully entitled to do so, shall suffer the penalty ofprision correctionalin its minimum and medium periods.