(a) Any municipality; any board, commission, or other authority duly established by ordinance of any municipality; the boards of trustees, respectively, of the firemen's relief and pension fund and the policemen's pension and relief fund of any municipality, or any county; or the board of trustees of any retirement system created by the General Assembly, in its discretion, may invest any of its funds not immediately needed for its purposes in the revenue bonds issued under the provisions of this chapter.
(b) Revenue bonds issued under this chapter shall be eligible to secure the deposit of public funds.