contract FinalizableCrowdsale is Crowdsale {
    using SafeMath for uint256;

    bool isFinalized = false;

    event Finalized();

    /**
     * @dev Must be called after crowdsale ends, to do some extra finalization
     * work. Calls the contract's finalization function.
     */
    function finalizeCrowdsale() onlyOwner public {
        require(!isFinalized);
        require(hasEnded());

        finalization();
        emit Finalized();

        isFinalized = true;
    }


    /**
     * @dev Can be overridden to add finalization logic. The overriding function
     * should call super.finalization() to ensure the chain of finalization is
     * executed entirely.
     */
    function finalization() internal {
    }
}
function finalization() internal {
}

/**
 * @dev Can be overridden to add finalization logic. The overriding function
 * should call super.finalization() to ensure the chain of finalization is
 * executed entirely.
 */