code: def make_ref_bundle(x):
      return make_ref_bundles([[x]])[0]
  
imports: import collections
  import time
  from unittest.mock import MagicMock
  import pytest
  import ray
  from ray._private.test_utils import run_string_as_driver_nonblocking, wait_for_condition
  from ray.data._internal.execution.interfaces import ExecutionOptions, ExecutionResources, PhysicalOperator
  from ray.data._internal.execution.interfaces.physical_operator import MetadataOpTask
  from ray.data._internal.execution.operators.input_data_buffer import InputDataBuffer
  from ray.data._internal.execution.operators.map_operator import MapOperator
  from ray.data._internal.execution.operators.map_transformer import create_map_transformer_from_block_fn
  from ray.data._internal.execution.streaming_executor import _debug_dump_topology, _validate_dag
  from ray.data._internal.execution.streaming_executor_state import AutoscalingState, DownstreamMemoryInfo, OpState, TopologyResourceUsage, _execution_allowed, build_streaming_topology, process_completed_tasks, select_operator_to_run, update_operator_states
  from ray.data._internal.execution.util import make_ref_bundles
  from ray.data.tests.conftest import *
  from ray.util.scheduling_strategies import NodeAffinitySchedulingStrategy
label_desc: Use image node_id 3 for calling a global function with example usage: make_ref_bundle(x) and returns: make_ref_bundles