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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 sortByIndex(self, index):

 """Implement a Index sort."""

        self.table_level.horizontalHeader().setSortIndicatorShown(True)
        sort_order = self.table_level.horizontalHeader().sortIndicatorOrder()
        self.table_index.model().sort(index, sort_order)
        self._sort_update()