No person shall park or leave standing a motor vehicle in or upon any parkway, public park, public school site, or other off street property of the city, or of the Beverly Hills Unified School District, or of any public utility, except as otherwise provided in this code, unless such person first shall have obtained permission for use of such property. Such permission may be evidenced in writing or by a sign or other physical evidence of invitation or permission to park thereon. (1962 Code § 3-6.2201)