law add_swap
import minebender-game@1.0.0.0/proof_base.bend as ProofBaseimport Base
679law add_swap:
680 for +a: Nat
681 for +b: Nat
682 for +c: Nat
683 for +d: Nat
684 {Nat.add(Nat.add(a, b), Nat.add(c, d)) == Nat.add(Nat.add(a, c), Nat.add(b, d)) : Nat}