∀ {C : Type u₁} [inst : CategoryTheory.Category.{v₁, u₁} C] {A B : C}
  [inst_1 : CategoryTheory.Limits.HasBinaryProduct A B],
  CategoryTheory.CategoryStruct.comp (CategoryTheory.Limits.opProdIsoCoprod A B).inv.unop
      CategoryTheory.Limits.coprod.inl.unop =
    CategoryTheory.Limits.prod.fst