∀ (X Y : Type u_1),
  CategoryTheory.CategoryStruct.comp
      ({ app := fun Z z x => (x, z), naturality := ⋯ }.app ((CategoryTheory.coyoneda.obj (Opposite.op X)).obj Y))
      ((CategoryTheory.coyoneda.obj (Opposite.op X)).map ({ app := fun x xf => xf.2 xf.1, naturality := ⋯ }.app Y)) =
    CategoryTheory.CategoryStruct.id ((CategoryTheory.coyoneda.obj (Opposite.op X)).obj Y)