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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 ensure_has_same_campaigns(self):
 """Ensure that the 2 campaigns to merge have been generated from the same campaign.yaml """

        lhs_yaml = osp.join(self.lhs, 'campaign.yaml')
        rhs_yaml = osp.join(self.rhs, 'campaign.yaml')
        assert osp.isfile(lhs_yaml)
        assert osp.isfile(rhs_yaml)
        assert filecmp.cmp(lhs_yaml, rhs_yaml)