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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 find_for_event(cls, event, include_hidden=False, **kwargs):
 """Returns a Query that retrieves the chatrooms for an event :param event: an indico event (with a numeric ID) :param include_hidden: if hidden chatrooms should be included, too :param kwargs: extra kwargs to pass to ``find()`` """

        query = cls.find(event_id=event.id, **kwargs)
        if not include_hidden:
            query = query.filter(~cls.hidden)
        return query