{C : Type u} →
  [inst : CategoryTheory.Category.{v, u} C] →
    {ι : Type w} →
      {I : CategoryTheory.Limits.MultispanIndex (CategoryTheory.Limits.MultispanShape.prod ι) C} →
        (iso : (i j : ι) → I.left (i, j) ≅ I.left (j, i)) →
          (∀ (i j : ι), CategoryTheory.CategoryStruct.comp (iso i j).hom (I.fst (j, i)) = I.snd (i, j)) →
            (∀ (i j : ι), CategoryTheory.CategoryStruct.comp (iso i j).hom (I.snd (j, i)) = I.fst (i, j)) →
              (∀ (i : ι), I.fst (i, i) = I.snd (i, i)) → I.SymmStruct