proposition: Corollary ZeroArrowUnique (Z : Zero) (c d : C) (f : C⟦c, ZeroObject Z⟧) (g : C⟦ZeroObject Z, d⟧) : f · g = ZeroArrow Z c d.
proof: Proof. rewrite (ZeroArrowToUnique Z c f). rewrite (ZeroArrowFromUnique Z d g). apply idpath. Defined.
imports: UniMath.Foundations.PartD UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Limits.Graphs.Colimits UniMath.CategoryTheory.Limits.Graphs.Limits UniMath.CategoryTheory.Limits.Graphs.Initial UniMath.CategoryTheory.Limits.Graphs.Terminal UniMath.CategoryTheory.Limits.Zero