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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 _handle_event(self, connection, event):
 """ Handle an Event event incoming on ServerConnection connection. """

        with self.mutex:
            matching_handlers = sorted(
                self.handlers.get("all_events", [])
                + self.handlers.get(event.type, [])
            )
            for handler in matching_handlers:
                result = handler.callback(connection, event)
                if result == "NO MORE":
                    return