∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] {X Y Z : C} (f : X ⟶ Y) (g : Y ⟶ Z),
  CategoryTheory.FreeGroupoid.homRel C ((Quiver.FreeGroupoid.of C).map (CategoryTheory.CategoryStruct.comp f g))
    (CategoryTheory.CategoryStruct.comp ((Quiver.FreeGroupoid.of C).map f) ((Quiver.FreeGroupoid.of C).map g))