let remotepubkey = keys.pubkeys().payment_point;
let witness_script = Address::p2pkh(&::bitcoin::PublicKey{compressed: true, key: remotepubkey}, Network::Testnet).script_pubkey();
let sighash = Message::from_slice(&bip143::SigHashCache::new(&spend_tx).signature_hash(0, &witness_script, output.value, SigHashType::All)[..]).unwrap();
let remotepubkey = keys.pubkeys().payment_point;
let witness_script = Address::p2pkh(&::bitcoin::PublicKey{compressed: true, key: remotepubkey}, Network::Testnet).script_pubkey();
let sighash = Message::from_slice(&bip143::SigHashCache::new(&spend_tx).signature_hash(0, &witness_script, output.value, SigHashType::All)[..]).unwrap();