fact: Definition ϕ₁ {a b : C} (f : folds_iso_data a b) {x : C} : (x ⇒ a) ≃ (x ⇒ b) := pr1 (pr1 f) x.
imports: UniMath.Folds.UnicodeNotations UniMath.Foundations.PartD UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.Foundations.UnivalenceAxiom UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.Folds.folds_precat UniMath.Folds.from_precats_to_folds_and_back