code: def _GetRow(self, columns=None):
          
  
          row = self._table[self._row_index]
          if columns:
              result = []
              for col in columns:
                  if col not in self.header:
                      raise TableError("Column header %s not known in table." % col)
                  result.append(row[self.header.index(col)])
              row = result
          return row
docs: Returns the current row as a tuple.