code: def collect_state(self):
      global _XVAL
      return _XVAL
  
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 1 for calling the XValStateSaver obj's underlying member method code with example usage: obj.collect_state() and returns: _XVAL