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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 get_items(self, scenario_id):
 """ Get all the items in this group, in the given scenario """

        items = get_session().query(ResourceGroupItem)\
                .filter(ResourceGroupItem.group_id==self.id).\
                filter(ResourceGroupItem.scenario_id==scenario_id).all()

        return items