code: def open_attributes_file(self):
          '''
          Called during initialization. Only needs to be explicitly
          called if save_and_close_attributes is explicitly called
          beforehand.
          '''
          if not self.saveable():
              raise AttributeError("Cannot open attribute file without a valid file")
          if self._db_closed:
              self._fd = FileDict(self._file_name, db_ext=self._db_ext,
                                     read_only=self._read_only, clear=False, cache_size=0,
                                     immutable_vals=False, stringify_keys=False,
                                     cache_misses=False)
              self._db_closed = Falsf open_attributes_file(self):
          '''
          Called during initialization. Only needs to be explicitly
          called if save_and_close_attributes is explicitly called
          beforehand.
          '''
          if not self.saveable():
              raise AttributeError("Cannot open attribute file without a valid file")
          if self._db_closed:
              self._fd = FileDict(self._file_name, db_ext=self._db_ext,
                                     read_only=self._read_only, clear=False, cache_size=0,
                                     immutable_vals=False, stringify_keys=False,
                                     cache_misses=False)
              self._db_closed = False
docs: Called during initialization. Only needs to be explicitly
          called if save_and_close_attributes is explicitly called
          beforehand.