let sighash = ignore_error!(Message::from_slice(&sighash_parts.sighash_all(&input, &htlc_redeemscript, values_drain.next().unwrap())[..]));
let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));
let sighash = ignore_error!(Message::from_slice(&sighash_parts.sighash_all(&input, &htlc_redeemscript, values_drain.next().unwrap())[..]));
let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key));