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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 trigger(self, event: str, *args: T.Any, **kw: T.Any) -> bool: """Triggers all handlers which are subscribed to an event. Returns True when there were callbacks to execute, False otherwise."""


        callbacks = list(self._events.get(event, []))
        if not callbacks:
            return False

        for callback in callbacks:
            callback(*args, **kw)
        return True