There shall be a provision that a copy of the application, if any, of the policyholder shall be attached to the policy when issued and become a part of the contract; that all statements made by the policyholder or by the persons insured shall be deemed representations and not warranties, and that no statement made by any person insured shall be used in any contest unless a copy of the instrument containing the statement is or has been furnished to such person or to his or her beneficiary.