'Internal interface for engine-to-engine communication via RPC.
Allows an additional option which should not be exposed to users via
the API:
:param template_id: the ID of a pre-stored template in the DB'

def _update_stack(self, ctxt, stack_identity, template, params, files, args, environment_files=None, template_id=None):

    return self.call(ctxt, self.make_msg('update_stack', stack_identity=stack_identity, template=template, params=params, files=files, environment_files=environment_files, args=args, template_id=template_id), version='1.29')
