code: def test_pickle(self):
      x = dmatrix("x")
      y = dmatrix("y")
  
      m = mul(x, y)
  
      s = pickle.dumps(m)
      m2 = pickle.loads(s)
  
      assert m2.owner.op == m.owner.op
  
file_path: pytensor/tests/compile/test_ops.py
imports: import pickle
  import numpy
  from pytensor import function
  from pytensor.compile.ops import as_op
  from pytensor.tensor.type import dmatrix, dvector
  from tests import unittest_tools
label_desc: Use image node_id 4 for calling the TestOpDecorator obj's underlying member method code with example usage: obj.test_pickle() without return types