code: def updateItemData(self, item, index):
          
          from projexui.widgets.xganttwidget.xganttwidgetitem import XGanttWidgetItem
          if not isinstance(item, XGanttWidgetItem):
              return
          
          value = unwrapVariant(item.data(index, Qt.EditRole))
          
          if type(value) == QDateTime:
              value = value.date()
              item.setData(index, Qt.EditRole, wrapVariant(value))
          
          if type(value) == QDate:
              value = value.toPython()
          
          columnName = self.treeWidget().columnOf(index)
          item.setProperty(columnName, value)
          item.sync()
docs: Updates the item information from the tree.
          
          :param      item    | <XGanttWidgetItem>
                      index   | <int>