Notwithstanding any other provision of law, any civil action challenging the constitutionality of section 534
of this title or any provision thereof shall be heard by a district court of three judges convened pursuant to the provisions of section 2284
of title 28
Notwithstanding any other provision of law, an interlocutory or final judgment, decree, or order of the court of three judges in an action under paragraph (1) holding section 534
of this title or any provision thereof unconstitutional shall be reviewable as a matter of right by direct appeal to the Supreme Court. Any such appeal shall be filed not more than 20 days after entry of such judgment, decree, or order.