code: def test_plates(self):
      assert self.plates == self.model_graph.get_plates()
  
imports: import warnings
  import numpy
  import pytensor
  import pytensor.tensor
  import pytest
  from pytensor.compile.sharedvalue import SharedVariable
  from pytensor.tensor.variable import TensorConstant
  import pymc
  from pymc.exceptions import ImputationWarning
  from pymc.model_graph import ModelGraph, model_to_graphviz, model_to_networkx
label_desc: Use image node_id 4 for calling the BaseModelGraphTest obj's underlying member method code with example usage: obj.test_plates() without return types