code: def _get_bundles(bundle: RefBundle):
      output = []
      for block, _ in bundle.blocks:
          output.extend(list(ray.get(block)["id"]))
      return output
  
imports: import collections
  import random
  import time
  from typing import Any, Iterable, List
  from unittest.mock import MagicMock
  import numpy
  import pandas
  import pytest
  import ray
  from ray._private.test_utils import wait_for_condition
  from ray.data._internal.compute import ActorPoolStrategy, TaskPoolStrategy
  from ray.data._internal.execution.interfaces import ExecutionOptions, PhysicalOperator, RefBundle
  from ray.data._internal.execution.operators.actor_pool_map_operator import ActorPoolMapOperator
  from ray.data._internal.execution.operators.base_physical_operator import AllToAllOperator
  from ray.data._internal.execution.operators.input_data_buffer import InputDataBuffer
  from ray.data._internal.execution.operators.limit_operator import LimitOperator
  from ray.data._internal.execution.operators.map_operator import MapOperator, _BlockRefBundler
  from ray.data._internal.execution.operators.map_transformer import create_map_transformer_from_block_fn
  from ray.data._internal.execution.operators.output_splitter import OutputSplitter
  from ray.data._internal.execution.operators.task_pool_map_operator import TaskPoolMapOperator
  from ray.data._internal.execution.operators.union_operator import UnionOperator
  from ray.data._internal.execution.util import make_ref_bundles
  from ray.data.block import Block
  from ray.data.context import DataContext
  from ray.data.tests.util import run_one_op_task, run_op_tasks_sync
  from ray.tests.conftest import *
label_desc: Use image node_id 21 for calling a global function with example usage: _get_bundles(bundle) and returns: output