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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 choice(self, queues, connection):
 """ Chooses a random queue for messages to specified connection. @param queues: A C{dict} mapping queue name to queues (sets of frames) to which specified connection is subscribed. @type queues: C{dict} of C{str} to C{set} of L{stompclient.frame.Frame} @param connection: The connection that is going to be delivered the frame(s). @type connection: L{coilmq.server.StompConnection} @return: A random queue destination or None if list is empty. @rtype: C{str} """

        if not queues:
            return None
        return random.choice(list(queues.keys()))