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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_catalog_hierarchy_id(self, catalog_id, proxy, runtime):
 """Gets the catalog hierarchy"""

        seed_str = convert_catalog_id_to_object_id_string(catalog_id)
        ident = Id(authority=self._authority,
                   namespace='hierarchy.Hierarchy',
                   identifier=seed_str)
        return HierarchyLookupSession(proxy, runtime).get_hierarchy(ident).get_id()