Scope.

This chapter deals with the taxation of estates and trusts and their beneficiaries. This chapter does not apply to any trust which, under the governing instrument and applicable State law, is revocable by the settlor. In such case, the settlor shall be deemed to be the recipient of the income or gains of the trust. The term trust, as used in this chapter, does not apply to any business trust including any trust treated as a real estate investment trust for Federal income tax purposes.