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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 listen(self, once=False):
 """Listen for changes in all registered listeners. Use add_listener before calling this funcion to listen for desired events or set `once` to True to listen for initial room information """


        if once:
            # we listen for time event and return false so our
            # run_queues function will be also falsy and break the loop
            self.add_listener("time", lambda _: False)
        return self.conn.listen()