(debtor was beneficiary of 50 percent of tax-deferred annuity owned by decedent; upon decedent's death, debtor inherited account funds and rolled them over into IRA in name of decedent for debtor's benefit; one day before decedent's death, debtor filed Chapter 7 and claimed the IRA account as exempt; funds held to be exempt; 11 U.S.C. Sec. 522(d)(12) does not require retirement funds originally to have been set apart by the debtor in contemplation of debtor's retirement; inherited IRAs are "retirement funds" as phrase used in 11 U.S.C. Sec. 522(d)(12); funds in account are tax-exempt under I.R.C. (here I.R.C. Sec. 408) as required by 11 U.S.C. Sec. 522(d)(12)).