code: def remove_gateway_router(self, router):
          '''
          Removes an external network gateway from the specified router
          '''
          router_id = self._find_router_id(router)
          return self.network_conn.remove_gateway_router(router=router_idf remove_gateway_router(self, router):
          '''
          Removes an external network gateway from the specified router
          '''
          router_id = self._find_router_id(router)
          return self.network_conn.remove_gateway_router(router=router_id)
docs: Removes an external network gateway from the specified router