code: def reorder(self, single_column=False):
          
          if single_column:
              columns = self.sortOrder[:1]
          else:
              columns = self.sortOrder
          for ascending,column in columns[::-1]:
              # Python 2.2+ guarantees stable sort, so sort by each column in reverse 
              # order will order by the assigned columns 
              self.sorted.sort( key=column.get, reverse=(not ascending))
docs: Force a reorder of the displayed items