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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 _all_queue_names(self):
 """ Return a list of all unique queue names in our config. :return: list of all queue names (str) :rtype: :std:term:`list` """

        queues = set()
        endpoints = self.config.get('endpoints')
        for e in endpoints:
            for q in endpoints[e]['queues']:
                queues.add(q)
        return sorted(queues)