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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_service_list(self) -> list: """Get a list of docker services. Only the manager nodes can retrieve all the services Returns: list, all the ids of the services in swarm """

        # Initialising empty list
        services = []

        # Raise an exception if we are not a manager
        if not self._manager:
            raise RuntimeError('Only the Swarm manager node can retrieve'
                               ' all the services.')

        service_list = self._client.services.list()
        for s_list in service_list:
            services.append(s_list.short_id)
        return services