def GetRootKey(self):
regf_key = self._regf_file.get_root_key()<EOL>if not regf_key:<EOL><INDENT>return None<EOL><DEDENT>return REGFWinRegistryKey(regf_key, key_path=self._key_path_prefix)<EOL>
Retrieves the root key.

        Returns:
          WinRegistryKey: Windows Registry root key or None if not available.