It is declared that it is illegal for any person, persons, or firms to park, stand or leave standing any vehicle, either occupied or not otherwise than temporarily, for the purpose of and while actually engaged in loading and unloading of passengers or materials on 7th Street between G Street and Griffith Avenue, and on D Street, E Street, and F Street between 6th and 8th Streets, in the city, between the hours of three a.m. and five a.m. (Ord. 82 §1, 1958).