Removes the top level item at the inputed index from the widget.
        
        :param      index | <int>
        
        :return     <XGanttWidgetItem> || None

def takeTopLevelItem( self, index ):
        """
        Removes the top level item at the inputed index from the widget.
        
        :param      index | <int>
        
        :return     <XGanttWidgetItem> || None
        """
        item = self.topLevelItem(index)
        if item:
            self.viewWidget().scene().removeItem(item.viewItem())
            self.treeWidget().takeTopLevelItem(index)
            
            return item
        return None