function requireTrade(address from) public view {
        require(!readOnly, "Read only mode engaged");

        uint256 i = 0;
        address current = addressLinkedList[0];
        while (current != 0) {
            if(current == from) {
                uint256 timestamp = freezeUntil[current];
                require(timestamp < block.timestamp, "Trades from your account are temporarily not possible. This is due to ICO rules.");

                break;
            }

            current = addressLinkedList[current];
            i++;
        }
    }