Set: pp::colors
  Set: pp::unicode
  Assumed: N
  Assumed: f
  Assumed: g
⊤ ++ ⊥ ++ ⊤
  Set: lean::pp::notation
f (f ⊤ ⊥) ⊤
  Assumed: a
  Assumed: b
g (g a b) a
f (f ⊤ ⊥) ⊥