def _load_waiters(
        self, attrs, resource_name, resource_model, service_context
    ):
        """
        Load resource waiters from the model. Each waiter allows you to
        wait until a resource reaches a specific state by polling the state
        of the resource.
        """
        for waiter in resource_model.waiters:
            attrs[waiter.name] = self._create_waiter(
                resource_waiter_model=waiter,
                resource_name=resource_name,
                service_context=service_context,
            )

        Load resource waiters from the model. Each waiter allows you to
        wait until a resource reaches a specific state by polling the state
        of the resource.
        
boto3/resources/factory.py