code: def pickleable_sqr(x):
      return x * x
  
file_path: agents/tf_agents/system/multiprocessing_test.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import pickle
  from tf_agents.system import system_multiprocessing
  from tf_agents.utils import test_utils
label_desc: Use image node_id 3 for calling a global function with example usage: pickleable_sqr(x) and returns: unknown