code: def _unpickle_sparse_frame_compat(self, state):
          
          series, cols, idx, fv, kind = state
  
          if not isinstance(cols, Index):  # pragma: no cover
              from pandas.io.pickle import _unpickle_array
              columns = _unpickle_array(cols)
          else:
              columns = cols
  
          if not isinstance(idx, Index):  # pragma: no cover
              from pandas.io.pickle import _unpickle_array
              index = _unpickle_array(idx)
          else:
              index = idx
  
          series_dict = DataFrame()
          for col, (sp_index, sp_values) in series.items():
              series_dict[col] = SparseSeries(sp_values, sparse_index=sp_index,
                                              fill_value=fv)
  
          self._data = to_manager(series_dict, columns, index)
          self._default_fill_value = fv
          self._default_kind = kind
docs: Original pickle format