keras/src/backend/tensorflow/core.py/Variable/_export_to_saved_model_graph
class Variable:    def _export_to_saved_model_graph(
        self, object_map, tensor_map, options, **kwargs
    ):
        resource_list = self.value._export_to_saved_model_graph(
            object_map, tensor_map, options, **kwargs
        )
        object_map[self] = tf.Variable(object_map[self.value])
        return resource_list