(a) by which any party thereto is restricted absolutely from enforcing his rights under or in respect of any contract, by the usual legal proceedings in the ordinary tribunals, or which limits the time within which he may thus enforce his rights; or
(b) which extinguishes the rights of any party thereto, or discharges any party thereto from any liability, under or in respect of any contract on the expiry of a specified period so as to restrict any party from enforcing his rights, is void to that extent.]
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