code: def mutate(self, model):
      pool1 = model.graphs["stem"].get_node_by_name("pool1")
      op = self.choice(self.ops)
      pool1.update_operation(op)
  
      pool2 = model.graphs["stem"].get_node_by_name("pool2")
      if op == self.ops[0]:
          pool2.update_operation(self.ops[0])
      else:
          pool2.update_operation(self.choice(self.ops))
  
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 2 for calling the DebugMutator obj's underlying member method code with example usage: obj.mutate(model) without return types