(a) Any municipality or any board, commission, or other authority established by ordinance of any municipality, or 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 may, in its discretion, invest any of its funds not immediately needed for its purposes in the revenue bonds issued under the provisions of this subchapter.
(b) Revenue bonds issued under this subchapter shall be eligible to secure the deposit of public funds.