The purpose of this part is to recodify and supplant previously enacted provisions of law which authorize cities to levy assessments on businesses within a parking and business improvement area and to provide a uniform procedure to levy assessments for improvements and activities of businesses located and operating in a business district of a city. This part does not affect or limit any other provisions of law authorizing or providing for the furnishing of improvements or activities or the raising of revenue for these purposes. In addition, this part is intended to provide a method for financing public programs to attract tourist visits to areas where tourism is economically important and desired.