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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 emit(self, event, *event_args):
 """Call the registered listeners for ``event``. The listeners will be called with any extra arguments passed to :meth:`emit` first, and then the extra arguments passed to :meth:`on` """

        listeners = self._listeners[event][:]
        for listener in listeners:
            args = list(event_args) + list(listener.user_args)
            result = listener.callback(*args)
            if result is False:
                self.off(event, listener.callback)