def get_internal_queue(self, thread_id):
        """ returns internal command queue for a given thread.
        if new queue is created, notify the RDB about it """
        if thread_id.startswith('__frame__'):
            thread_id = thread_id[thread_id.rfind('|') + 1:]
        return self._cmd_queue[thread_id]
returns internal command queue for a given thread.
        if new queue is created, notify the RDB about it