No person shall interfere with or obstruct in any way any police officer, or officer or employee of this city in their performance of the provisions of this title.  The removal, obliteration or concealment of any chalk mark or other distinguishing mark used by any police, other employee or officer of this city in connection with the enforcement of the parking regulations of this chapter shall, if done for the purpose of evading the provisions of this title, constitute such interference or obstruction.  (Ord. 486 § 4 (part), 1992:  prior code § 13-3.4)