code: def _get_pools(model):
      pool1 = model.graphs["stem"].get_node_by_name("pool1").operation
      pool2 = model.graphs["stem"].get_node_by_name("pool2").operation
      return pool1, pool2
  
imports: import json
  from pathlib import Path
  import pytest
  from nni.common.framework import get_default_framework, set_default_framework
  from nni.nas.space import StationaryMutator, Mutator, MutationSampler, GraphModelSpace, ModelStatus, MutatorSequence
  from nni.nas.space.mutator import _RandomSampler
  from nni.nas.space.graph_op import Operation
label_desc: Use image node_id 14 for calling a global function with example usage: _get_pools(model) and returns: pool1,  pool2