function exchangeNominsForHavvens(uint nominAmount)
        public 
        pricesNotStale
        notPaused
        returns (uint) 
    {
        
        uint havvensToSend = havvensReceivedForNomins(nominAmount);
        
        
        nomin.transferFrom(msg.sender, this, nominAmount);

        
        havven.transfer(msg.sender, havvensToSend);

        emit Exchange("nUSD", nominAmount, "HAV", havvensToSend);

        return havvensToSend; 
    }