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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _setup_file_hierarchy_limit( self, files_count_limit, files_size_limit, temp_dir, cgroups, pid_to_kill):
 """Start thread that enforces any file-hiearchy limits."""

        if files_count_limit is not None or files_size_limit is not None:
            file_hierarchy_limit_thread = FileHierarchyLimitThread(
                self._get_result_files_base(temp_dir),
                files_count_limit=files_count_limit,
                files_size_limit=files_size_limit,
                cgroups=cgroups,
                pid_to_kill=pid_to_kill,
                callbackFn=self._set_termination_reason,
                kill_process_fn=self._kill_process)
            file_hierarchy_limit_thread.start()
            return file_hierarchy_limit_thread
        return None