code: def new(self, extension_sequence):
          # type: (int) -> None
          '''
          Create a new Rock Ridge Extension Selector record.
  
          Parameters:
           extension_sequence - The sequence number of this extension.
          Returns:
           Nothing.
          '''
          if self._initialized:
              raise pycdlibexception.PyCdlibInternalError('ES record already initialized!')
  
          self.extension_sequence = extension_sequence
          self._initialized = Truf new(self, extension_sequence):
          # type: (int) -> None
          '''
          Create a new Rock Ridge Extension Selector record.
  
          Parameters:
           extension_sequence - The sequence number of this extension.
          Returns:
           Nothing.
          '''
          if self._initialized:
              raise pycdlibexception.PyCdlibInternalError('ES record already initialized!')
  
          self.extension_sequence = extension_sequence
          self._initialized = True
docs: Create a new Rock Ridge Extension Selector record.
  
          Parameters:
           extension_sequence - The sequence number of this extension.
          Returns:
           Nothing.