code: def _GetElementDataTypeDefinition(self, data_type_definition):
      
      if not data_type_definition:
        raise errors.FormatError('Missing data type definition')
  
      element_data_type_definition = getattr(
          data_type_definition, 'element_data_type_definition', None)
      if not element_data_type_definition:
        raise errors.FormatError(
            'Invalid data type definition missing element')
  
      return element_data_type_definition
docs: Retrieves the element data type definition.
  
      Args:
        data_type_definition (DataTypeDefinition): data type definition.
  
      Returns:
        DataTypeDefinition: element data type definition.
  
      Raises:
        FormatError: if the element data type cannot be determined from the data
            type definition.