∀ {J : Type v} [inst : CategoryTheory.Category.{w, v} J] (F : CategoryTheory.Functor J TopCat)
  [inst_1 : CategoryTheory.Limits.HasColimit F] (U : Set ↑(CategoryTheory.Limits.colimit F)),
  IsOpen U ↔ ∀ (j : J), IsOpen (⇑(CategoryTheory.ConcreteCategory.hom (CategoryTheory.Limits.colimit.ι F j)) ⁻¹' U)