Please explain U.S. code section 956 D and E

(d)Pledges and guarantees

For purposes of subsection (a), a controlled foreign corporation shall, under regulations prescribed by the Secretary, be considered as holding an obligation of a United States person if such controlled foreign corporation is a pledgor or guarantor of such obligations.

(e)Regulations

The Secretary shall prescribe such regulations as may be necessary to carry out the purposes of this section, including regulations to prevent the avoidance of the provisions of this section through reorganizations or otherwise.