code: def rowkey(self, row):
          'returns a tuple of the key for the given row'
          return tuple(c.getTypedValueOrException(row) for c in self.keyColsf rowkey(self, row):
          'returns a tuple of the key for the given row'
          return tuple(c.getTypedValueOrException(row) for c in self.keyCols)
docs: returns a tuple of the key for the given row