code: def _initialize_variables(test_case, scaffold):
      """Initializes variables for a session.
  
      Args:
        test_case: A TensorFlowTestCase object.
        scaffold: A train.Scaffold object.
      """
      scaffold.finalize()
      test_case.assertIsNone(scaffold.init_feed_dict)
      test_case.assertIsNone(scaffold.init_fn)
      scaffold.init_op.run()
      scaffold.ready_for_local_init_op.eval()
      scaffold.local_init_op.run()
      scaffold.ready_op.eval()
      test_case.assertIsNotNone(scaffold.saver)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import tensorflow
  from tensorflow import estimator
  from tensorflow_ranking.python import head
  from tensorflow_ranking.python import metrics
label_desc: Use image node_id 1 for calling a global function with example usage: _initialize_variables(test_case, scaffold) without return types