code: def GetSizeHint(self, context=None, **unused_kwargs):
      
      context_state = getattr(context, 'state', {})
  
      elements_data_size = self.GetByteSize()
      if elements_data_size:
        return elements_data_size
  
      try:
        elements_data_size = self._CalculateElementsDataSize(context)
      except errors.MappingError:
        pass
  
      if elements_data_size is None and self._HasElementsTerminator():
        size_hints = context_state.get('size_hints', {})
        size_hint = size_hints.get(self._data_type_definition.name, None)
  
        elements_data_size = 0
  
        if size_hint:
          elements_data_size = size_hint.byte_size
  
        if not size_hint or not size_hint.is_complete:
          elements_data_size += self._element_data_type_definition.GetByteSize()
  
      return elements_data_size
docs: Retrieves a hint about the size.
  
      Args:
        context (Optional[DataTypeMapContext]): data type map context, used to
            determine the size hint.
  
      Returns:
        int: hint of the number of bytes needed from the byte stream or None.