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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 verified_pairs(self):
        '''
        Returns all lineage Pair objects that contain verified pairings.
        '''
        if not hasattr(self.just_pairs[0], 'verified'):
            self.verify_light_chains()
        return [p for p in self.just_pairs if p.verified]