code: def _find_old_style_function(outputs):
      """Find old-style functions in the computational graph."""
      found = []
      for v in outputs:
          assert isinstance(
              v, (chainer.Variable, chainer.variable.VariableNode)
          )
          if v.creator is None:
              continue
          if isinstance(v.creator, chainer.Function):
              found.append(v.creator)
          else:
              assert isinstance(v.creator, chainer.FunctionNode)
          found.extend(_find_old_style_function(v.creator.inputs))
      return found
  
imports: import collections
  import itertools
  from logging import getLogger
  import random
  import chainer
  import chainer.functions
  import numpy
  import chainerrl
  from chainerrl import agent
  from chainerrl.agents.ppo import _compute_explained_variance
  from chainerrl.agents.ppo import _make_dataset
  from chainerrl.agents.ppo import _make_dataset_recurrent
  from chainerrl.agents.ppo import _yield_subset_of_sequences_with_fixed_number_of_items
  from chainerrl.misc.batch_states import batch_states
label_desc: Use image node_id 9 for calling a global function with example usage: _find_old_style_function(outputs) and returns: found