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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 on(self, event_name, callback):

 """Register callback for a SocketIO event."""

        if not event_name:
            return False

        _LOGGER.debug("Adding callback for event name: %s", event_name)

        self._callbacks[event_name].append((callback))

        return True