code: def test_1(self):
      # Then, build a mode with the same linker, and a modified optimizer
      default_mode = theano.compile.mode.get_default_mode()
      modified_mode = default_mode.including("specialize")
  
      # The following line used to fail, with Python 2.4, in July 2012,
      # because an fgraph was associated to the default linker
      copy.deepcopy(modified_mode)
  
      # More straightforward test
      linker = theano.compile.mode.get_default_mode().linker
      assert not hasattr(linker, "fgraph") or linker.fgraph is None
  
file_path: Theano/theano/compile/tests/test_modes.py
imports: from __future__ import absolute_import, print_function, division
  import copy
  import unittest
  import theano
  import theano.tensor
  from theano.compile import Mode
label_desc: Use image node_id 1 for calling the T_old_problem obj's underlying member method code with example usage: obj.test_1() without return types