§ 5-321. Agreements exempting lessors from liability for negligence void and unenforceable. Every covenant, agreement or understanding in or in connection with or collateral to any lease of real property exempting the lessor from liability for damages for injuries to person or property caused by or resulting from the negligence of the lessor, his agents, servants or employees, in the operation or maintenance of the demised premises or the real property containing the demised premises shall be deemed to be void as against public policy and wholly unenforceable.