Lean4
/-- The map part of the functor `CondensedSet ⥤ TopCat` -/
@[simps!]
def toTopCatMap : X.toTopCat ⟶ Y.toTopCat :=
TopCat.ofHom
{ toFun := f.val.app ⟨of PUnit⟩
continuous_toFun := by
rw [continuous_coinduced_dom]
apply continuous_sigma
intro ⟨S, x⟩
simp only [Function.comp_apply, coinducingCoprod]
rw [show (fun (a : S) ↦ f.val.app ⟨of PUnit⟩ (X.val.map ((of PUnit.{u + 1}).const a).op x)) = _ from
funext fun a ↦ NatTrans.naturality_apply f.val ((of PUnit.{u + 1}).const a).op x]
exact continuous_coinducingCoprod Y _ }