French-English translations for serpent

serpent
us
This is true - and I am simplifying to the point of caricature - for the free circulation of persons, which is a subject of endless, serpentine complications. C'est vrai, et de manière caricaturale, pour la libre circulation des personnes, véritable serpent de mer.
snake
us
They are like a snake biting its own tail. C'est comme un serpent qui se mord la queue. We have to be alert and watchful; beware of the eggs of the snake, as Ingmar Bergman taught us. Nous devons nous montrer alertes et vigilants; prendre garde à l'œuf du serpent, comme nous l'a appris Ingmar Bergman. We would therefore have a kind of corridor between 15% and 25%, somewhat like the currency snake in its day. Nous aurions donc une sorte de couloir entre 15% et 25%, un peu comme le serpent monétaire en son temps.