∀ (C : Type u) [inst : CategoryTheory.Category.{v, u} C] [inst_1 : CategoryTheory.Limits.HasColimits C] {X Y : TopCat}
  (f : X ⟶ Y) (F : TopCat.Presheaf C X) (x : ↑X),
  TopCat.Presheaf.stalkPushforward C f F x =
    CategoryTheory.CategoryStruct.comp
      (CategoryTheory.Limits.colim.map
        (CategoryTheory.Functor.whiskerRight
          (CategoryTheory.NatTrans.op (TopologicalSpace.OpenNhds.inclusionMapIso f x).inv) F))
      (CategoryTheory.Limits.colimit.pre
        (((CategoryTheory.Functor.whiskeringLeft (TopologicalSpace.OpenNhds x)ᵒᵖ (TopologicalSpace.Opens ↑X)ᵒᵖ C).obj
              (TopologicalSpace.OpenNhds.inclusion x).op).obj
          F)
        (TopologicalSpace.OpenNhds.map f x).op)