intro a
Γ : Type
inst✝ : Alphabet Γ
⊢ ∀ (b : (Term.algebra (RankedAlphabet.lift Γ) Empty).carrier), ∃ a, treeₑ a = b
Γ : Type
inst✝ : Alphabet Γ
a : (Term.algebra (RankedAlphabet.lift Γ) Empty).carrier
⊢ ∃ a_1, treeₑ a_1 = a