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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 sort(self, columnId, order=Qt.AscendingOrder):
 """ Sorts the model column After sorting the data in ascending or descending order, a signal `layoutChanged` is emitted. :param: columnId (int) the index of the column to sort on. :param: order (Qt::SortOrder, optional) descending(1) or ascending(0). defaults to Qt.AscendingOrder """

        self.layoutAboutToBeChanged.emit()
        self.sortingAboutToStart.emit()
        column = self._dataFrame.columns[columnId]
        self._dataFrame.sort_values(column, ascending=not bool(order), inplace=True)
        self.layoutChanged.emit()
        self.sortingFinished.emit()