A county may not levy a tax under this Part unless the county or at least one unit of local government in the county operates a public transportation system. As used in this Part, operation of a public transportation system includes a contract or interlocal agreement for operation of the public transportation system by another county or municipality, or by a transportation authority created under (i) a municipal charter; or (ii) Article 25, 26, or 27 of Chapter 160A of the N.C. Gen. Stat.. As used in this Part, operation of a public transportation system also includes a contract with a private entity for operation of the public transportation system. ?(2009-527, s. 2(b).)