Section, act June 17, 1930, ch. 497, title VII, 740, as added July 26, 1979, Pub. L. 96–39, title I, § 101, 93 Stat. 175, provided that the antidumping duty imposed by section 1673 of this title was to be treated as a normal customs duty for drawback purposes. See section 1677h of this title.