code: def showRemoveColumnDialog(self, triggered):
          
          if triggered:
              model = self.tableView.model()
              if model is not None:
                  columns = model.dataFrameColumns()
                  dialog = RemoveAttributesDialog(columns, self)
                  dialog.accepted.connect(self.removeColumns)
                  dialog.rejected.connect(self.uncheckButton)
                  dialog.show()
docs: Display the dialog to remove column(s) from the model.
  
          This method is also a slot.
  
          Args:
              triggered (bool): If the corresponding button was
                  activated, the dialog will be created and shown.