use crypto::digest::Digest;
use crypto::hkdf::{hkdf_extract,hkdf_expand};
-use crypto::sha2::Sha256;
use ln::msgs;
use ln::msgs::{HandleError, MsgEncodable};
use ln::chan_utils;
use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
use util::{transaction_utils,rng};
+use util::sha2::Sha256;
use std::default::Default;
use std::cmp;