code: def itemData(self, treeItem, column, role=Qt.DisplayRole):
          
          if role == Qt.DisplayRole:
              if column == self.COL_NODE_NAME:
                  return treeItem.nodeName
              elif column == self.COL_NODE_PATH:
                  return treeItem.nodePath
              elif column == self.COL_VALUE:
                  return treeItem.displayValue
              elif column == self.COL_DEF_VALUE:
                  return treeItem.displayDefaultValue
              elif column == self.COL_CTI_TYPE:
                  return type_name(treeItem)
              elif column == self.COL_DEBUG:
                  return treeItem.debugInfo
              else:
                  raise ValueError("Invalid column: {}".format(column))
  
          elif role == Qt.EditRole:
              if column == self.COL_VALUE:
                  return treeItem.data
              else:
                  raise ValueError("Invalid column: {}".format(column))
  
          elif role == Qt.ToolTipRole:
              if column == self.COL_NODE_NAME or column == self.COL_NODE_PATH:
                  return treeItem.nodePath
              elif column == self.COL_VALUE:
                  # Give Access to exact values. In particular in scientific-notation spin boxes
                  return repr(treeItem.configValue)
              elif column == self.COL_DEF_VALUE:
                  return treeItem.displayDefaultValue
              elif column == self.COL_CTI_TYPE:
                  return type_name(treeItem)
              elif column == self.COL_DEBUG:
                  return treeItem.debugInfo
              else:
                  return None
  
          elif role == Qt.CheckStateRole:
              if column != self.COL_VALUE:
                  # The CheckStateRole is called for each cell so return None here.
                  return None
              else:
                  return treeItem.checkState
          else:
              return super(ConfigTreeModel, self).itemData(treeItem, column, role=role)
docs: Returns the data stored under the given role for the item.