For this title an “annuity” is a contract, issued by a person which is not classified by the Internal Revenue Service as exempt from taxation under § 501(c)(3) of the Internal Revenue Code of 1954 [26 U.S.C. § 501(c)(3)], as subsequently amended, under which obligations are assumed as to periodic payments for specific term or terms or where the making or continuance of all or some such payments, or the amount of any such payment, is dependent upon continuance of human life. Such a contract which includes extra benefits of kinds set forth in §§ 902 (“life insurance” defined) and 903 (“health insurance” defined) of this title shall nevertheless be deemed to be an annuity if such extra benefits constitute a subsidiary or incidental part of the entire contract.