let mut weight_with_change: i64 = tx.get_weight() as i64 + 2 + witness_max_weight as i64 + change_len as i64 * 4;
// Include any extra bytes required to push an extra output.
weight_with_change += (VarInt(tx.output.len() as u64 + 1).len() - VarInt(tx.output.len() as u64).len()) as i64 * 4;
let mut weight_with_change: i64 = tx.get_weight() as i64 + 2 + witness_max_weight as i64 + change_len as i64 * 4;
// Include any extra bytes required to push an extra output.
weight_with_change += (VarInt(tx.output.len() as u64 + 1).len() - VarInt(tx.output.len() as u64).len()) as i64 * 4;