fact: Definition sig_equiv `{Equiv A} (P: A → Prop) : Equiv (sig P) := λ x y, `x = `y.
imports: MathClasses.theory.CoqStreams Coq.Classes.Morphisms Coq.Setoids.Setoid Coq.Program.Program Coq.Unicode.Utf8 Coq.Unicode.Utf8_core MathClasses.misc.stdlib_hints