∀ {C : Type u_2} [inst : CategoryTheory.Category.{u_1, u_2} C] [inst_1 : CategoryTheory.Limits.HasZeroMorphisms C]
  [inst_2 : CategoryTheory.Limits.HasBinaryBiproducts C] (P Q : C),
  CategoryTheory.CategoryStruct.comp
      (CategoryTheory.Limits.biprod.lift CategoryTheory.Limits.biprod.snd CategoryTheory.Limits.biprod.fst)
      (CategoryTheory.Limits.biprod.lift CategoryTheory.Limits.biprod.snd CategoryTheory.Limits.biprod.fst) =
    CategoryTheory.CategoryStruct.id (Q ⊞ P)