Any city or town in which a public utility district operates works, plants or facilities for the distribution and sale of electricity shall have the power to levy and collect from such district a tax on the gross revenues derived by such district from the sale of electricity within the city or town, exclusive of the revenues derived from the sale of electricity for purposes of resale. Such tax when levied shall be a debt of the district, and may be collected as such. Any such district shall have the power to add the amount of such tax to the rates or charges it makes for electricity so sold within the limits of such city or town.