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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_by_campaign(campaign_id, _connection=None, page_size=100, page_number=0, sort_by=enums.DEFAULT_SORT_BY, sort_order=enums.DEFAULT_SORT_ORDER):
 """ List all videos for a given campaign. """

        return connection.ItemResultSet(
            'find_videos_by_campaign_id', Video, _connection, page_size,
            page_number, sort_by, sort_order, campaign_id=campaign_id)