function _validateWithdraw(address _who, uint256 _id) internal view returns(bool) {
        require(!lockTokenStorage[_who][_id].finalized, "Full withdraw already exists");
        require(_combineArray(lockTokenStorage[_who][_id].tokens) > 0 , "This lockStorage is not exists");
        require(now > lockTokenStorage[_who][_id].periods[0], "Unlock time has not come");

        return true;
    }