def valid
import bend-collections@1.0.0.0/src/crypto/chacha/chacha20.bend as Chacha20import Base
137def valid(+key_bytes: List<&2, U32>, +nonce_bytes: List<&2, U32>, n: Nat) -> Bool:
138 Bool.and(has_length(key_bytes, 32n), has_length(nonce_bytes, n))