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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 associate(self, queue):
 """Merge this queue with another. Both queues will use a shared command list and either one can be used to fill or flush the shared queue. """

        assert isinstance(queue, GlirQueue)
        if queue._shared is self._shared:
            return

        # merge commands
        self._shared._commands.extend(queue.clear())
        self._shared._verbose |= queue._shared._verbose
        self._shared._associations[queue] = None
        # update queue and all related queues to use the same _shared object
        for ch in queue._shared._associations:
            ch._shared = self._shared
            self._shared._associations[ch] = None
        queue._shared = self._shared