code: def test_draw_computational_graph(self):
      x = chainer.Variable(np.zeros(5))
      y = x**2 + chainer.Variable(np.ones(5))
      dirname = tempfile.mkdtemp()
      filepath = os.path.join(dirname, "graph")
      chainerrl.misc.draw_computational_graph(y, filepath)
      self.assertTrue(os.path.exists(filepath + ".gv"))
      if chainerrl.misc.is_graphviz_available():
          self.assertTrue(os.path.exists(filepath + ".png"))
      else:
          self.assertFalse(os.path.exists(filepath + ".png"))
  
file_path: chainerrl/tests/misc_tests/test_draw_computational_graph.py
imports: import os
  import tempfile
  import unittest
  import chainer
  from chainer import testing
  import numpy
  import chainerrl
label_desc: Use image node_id 1 for calling the TestDrawComputationalGraph obj's underlying member method code with example usage: obj.test_draw_computational_graph() without return types