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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _previewFile(self):
 """Updates the preview widgets with new models for both tab panes. """

        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)