code: def GetSectionByIndex(self, section_index):
      
      if not self._is_parsed:
        self._Parse()
        self._is_parsed = True
  
      if section_index < 0 or section_index >= len(self._sections):
        return None
  
      return self._sections[section_index]
docs: Retrieves a specific section based on the index.
  
      Args:
        section_index (int): index of the section.
  
      Returns:
        VolumeExtent: a volume extent or None if not available.