To the extent practicable, special purpose revenue bonds issued pursuant to this part shall be issued to comply with requirements imposed by applicable federal law providing that the interest on the special purpose revenue bonds shall be excluded from gross income for federal income-tax purposes (except as certain minimum taxes or environmental taxes may apply). The director of finance may enter into agreements, establish funds or accounts, and take any action required to comply with applicable federal law. Nothing in this part shall be deemed to prohibit the issuance of special purpose revenue bonds, the interest on which may be included in gross income for federal income-tax purposes.