code: def resort(self, columnName):
          
          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
docs: 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.