code: def _parse_rmw_row_response(row_response):
      
      result = {}
      for column_family in row_response.row.families:
          column_family_id, curr_family = _parse_family_pb(column_family)
          result[column_family_id] = curr_family
      return result
docs: Parses the response to a ``ReadModifyWriteRow`` request.
  
      :type row_response: :class:`.data_v2_pb2.Row`
      :param row_response: The response row (with only modified cells) from a
                           ``ReadModifyWriteRow`` request.
  
      :rtype: dict
      :returns: The new contents of all modified cells. Returned as a
                dictionary of column families, each of which holds a
                dictionary of columns. Each column contains a list of cells
                modified. Each cell is represented with a two-tuple with the
                value (in bytes) and the timestamp for the cell. For example:
  
                .. code:: python
  
                    {
                        u'col-fam-id': {
                            b'col-name1': [
                                (b'cell-val', datetime.datetime(...)),
                                (b'cell-val-newer', datetime.datetime(...)),
                            ],
                            b'col-name2': [
                                (b'altcol-cell-val', datetime.datetime(...)),
                            ],
                        },
                        u'col-fam-id2': {
                            b'col-name3-but-other-fam': [
                                (b'foo', datetime.datetime(...)),
                            ],
                        },
                    }