code: def test_at_30(self):
      self.run_at_frame_rate(30)
  
file_path: lab/python/tests/episode_time_test.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  from absl.testing import absltest
  import numpy
  import six
  import deepmind_lab
label_desc: Use image node_id 3 for calling the EpisodeTimeTest obj's underlying member method code with example usage: obj.test_at_30() without return types