Sec. 20. EXEMPTION FROM LEGAL PROCESS; ASSIGNMENT OR TRANSFER. No portion of any such Pension System Fund, either before or after its order of disbursement by said Pension Board, and no amounts due or to become due any beneficiary or pensioner, under this Act, shall ever be held, seized, taken, subjected to, detained, or levied upon by virtue of any execution, attachment, garnishment, injunction, or other writ, and no order or decree, and no process or proceedings whatsoever, shall issue out of or by any court of this State for the payment of satisfaction, in whole or in part, out of said Pension System Fund, of any debt, damage, claim, demand, or judgment against any such members, pensioners, dependents, or any person whomsoever, nor shall such Pension System Fund or any part thereof, or any claim thereto, be directly or indirectly assigned or transferred. Any attempt to transfer or assign the same or any part thereof or any claim thereto shall be void. Said funds shall be sacredly held, kept, and disbursed for the purposes provided by this Act, and for no other purpose whatsoever.