It is unlawful for any person to sleep in any vehicle parked on the public street, alleyway or parking area, or any privately owned parking area, used for the parking of any customers of any business any day. "Vehicle," for the purpose of this section, is defined by Section 670 of the Vehicle Code of the state as it now exists or may hereafter be amended. (Ord. 1124 NCS §1, 1974.)