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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 resort(self, columnName):
 """ Re-sort the table. @param columnName: the name of the column to sort by. This is a string because it is passed from the browser. """

        csc = self.currentSortColumn
        newSortColumn = self.columns[columnName]
        if newSortColumn is None:
            raise Unsortable('column %r has no sort attribute' % (columnName,))
        if csc is newSortColumn:
            self.isAscending = not self.isAscending
        else:
            self.currentSortColumn = newSortColumn
            self.isAscending = True
        return self.isAscending