code: def GetSubkeyByIndex(self, index):
      
      if not self._registry_key and self._registry:
        self._GetKeyFromRegistry()
  
      subkeys = list(self._subkeys.values())
  
      if index < 0 or index >= len(subkeys):
        raise IndexError('Index out of bounds.')
  
      return subkeys[index]
docs: Retrieves a subkey by index.
  
      Args:
        index (int): index of the subkey.
  
      Returns:
        WinRegistryKey: Windows Registry subkey or None if not found.
  
      Raises:
        IndexError: if the index is out of bounds.