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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_relationships_by_search(self, relationship_query, relationship_search):
 """Pass through to provider RelationshipSearchSession.get_relationships_by_search"""

        # Implemented from azosid template for -
        # osid.resource.ResourceSearchSession.get_resources_by_search_template
        if not self._can('search'):
            raise PermissionDenied()
        return self._provider_session.get_relationships_by_search(relationship_query, relationship_search)