Case C-324/19: Judgment of the Court (Fourth Chamber) of 4 February 2021 (request for a preliminary ruling from the Finanzgericht Hamburg — Germany) — eurocylinder systems AG v Hauptzollamt Hamburg (Reference for a preliminary ruling — Common commercial policy — Anti-dumping duties — Regulation (EC) No 384/96 — Article 3(9) — Threat of material injury — Factors — Article 9(4) — Regulation (EC) No 926/2009 — Imports of certain seamless pipes and tubes of iron or steel originating in the People’s Republic of China — Invalidity)