simp only [list_direct_succ_set]
Node : Type
inst✝ : DecidableEq Node
g : Graph Node
xs : List Node
⊢ ↑(list_direct_succ_list g xs).toFinset = list_direct_succ_set g xs
Node : Type
inst✝ : DecidableEq Node
g : Graph Node
xs : List Node
⊢ ↑(list_direct_succ_list g xs).toFinset = {y | ∃ x ∈ xs, ∃ ys, y ∈ ys ∧ (x, ys) ∈ g}