pub fn create_asset(gnacs_code: String, initial_value: u256) -> Address {
    require(initial_value > 0, "Invalid initial value");
    return Address::new();
}

pub fn transfer_asset(asset_id: Address, to: Address) -> bool {
    require(!to.is_zero(), "Transfer to zero address");
    return true;
}

pub fn freeze_asset(asset_id: Address) -> bool {
    return true;
}

pub fn unfreeze_asset(asset_id: Address) -> bool {
    return true;
}