code: def _previewFile(self):
          
          dataFrame = self._loadCSVDataFrame()
          dataFrameModel = DataFrameModel(dataFrame, filePath=self._filename)
          dataFrameModel.enableEditing(True)
          self._previewTableView.setModel(dataFrameModel)
          columnModel = dataFrameModel.columnDtypeModel()
          columnModel.changeFailed.connect(self.updateStatusBar)
          self._datatypeTableView.setModel(columnModel)
docs: Updates the preview widgets with new models for both tab panes.