The driver of a public bus or a taxicab shall not park upon any street in the central business district at any place other than at a bus stop or taxicab stand, respectively, except that this provision shall not prevent the driver of any of these vehicles from temporarily stopping in accordance with other stopping or parking regulations at any place for the purpose of and while actually engaged in loading or unloading passengers.
('75 Code, § 42.30) Penalty, see § 73.99