code: def IsDefault(self):
      
      if not self._tsk_attribute or not self._file_system:
        return True
  
      if self._file_system.IsHFS():
        attribute_type = getattr(self._tsk_attribute.info, 'type', None)
        return attribute_type in (
            pytsk3.TSK_FS_ATTR_TYPE_HFS_DEFAULT, pytsk3.TSK_FS_ATTR_TYPE_HFS_DATA)
  
      if self._file_system.IsNTFS():
        return not bool(self.name)
  
      return True
docs: Determines if the data stream is the default data stream.
  
      Returns:
        bool: True if the data stream is the default data stream, false if not.