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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:

async def post_list(cls, sender, db, instances):
        '''
        Hook to capture the results of a list query.
        Useful when wanting to know when certain documents have come up in a query.
        Implement in resource subclasses to provide domain-specific behavior
        '''
        serialized_objects = await asyncio.gather(*[obj.serialize() for obj in instances])
        await cls.emit(db, 'resource_get_list', serialized_objects)