6.—(1) The duty which an occupier of premises owes to an entrant under this Act shall not be capable of being modified or excluded by a contract to which the entrant is a stranger, whether the occupier is bound by the contract to permit the entrant to enter or use the premises or not.

(2) For the purposes of this section, an entrant shall be deemed to be a stranger to a contract if the entrant is not for the time being entitled to the benefit of the contract as a party to it or as the successor by assignment or otherwise of a party to it, and, accordingly, a party to the contract who has ceased to be so entitled shall be deemed to be a stranger to the contract.

(3) This section applies to contracts entered into before the commencement of this Act, as well as to those entered into after such commencement.