No tax shall be imposed upon:
(A) Any person as to whom, or any occupancy as to which, it is beyond the power of the city to impose the tax provided in this subchapter.
(B) Any federal or state officer or employee when on official business.
(C) Any officer or employee of a foreign government who is exempt by reason of express provision of federal law or international treaty. No exemption shall be granted except upon a claim therefor made at the time rent is collected and under penalty of perjury upon a form prescribed by the City Manager.
('83 Code, § 3.28.040)