def _merge_on_matching(self, uuid, matcher, verbose):
        """Merge unique identity with uuid when a match is found"""

        matches = api.match_identities(self.db, uuid, matcher)

        new_uuid = uuid

        u = api.unique_identities(self.db, uuid)[0]

        for m in matches:
            if m.uuid == uuid:
                continue

            self._merge(u, m, verbose)

            new_uuid = m.uuid

            # Swap uids to merge with those that could
            # remain on the list with updated info
            u = api.unique_identities(self.db, m.uuid)[0]

        return new_uuid
Merge unique identity with uuid when a match is found