(a) Any city or town in this state or any board, commission, or other authority duly established by ordinance of any such city or town or the boards of trustees, respectively, of the firemen's relief and pension fund and the policemen's pension and relief fund of any such city or town may invest any of its funds not immediately needed for its purposes in the bonds or other obligations of any industrial or economic development corporation having its principal office in the county in which any such city or town is located.
(b) The board of trustees of any retirement system created by the General Assembly, in its discretion, may invest its funds in first lien coupon bonds of any corporation organized under the provisions of this act.