message: Update comments / logging
diff: @@ -20,6 +20,7 @@ move prediction and score estimation.
  from absl import flags
  import functools
  +import logging
  import os.path
  import sys
  @@ -144,7 +145,8 @@ class DualNetwork():
  with self.sess.graph.as_default():
  features, labels = get_inference_input()
  params = FLAGS.flag_values_dict()
  - # Tpu inference is supported on C++ only
  + logging.info('TPU inference is supported on C++ only. '
  + 'DualNetwork will ignore use_tpu=True')
  params['use_tpu'] = False
  estimator_spec = model_fn(features, labels,
  tf.estimator.ModeKeys.PREDICT,
  @@ -202,7 +204,7 @@ def model_fn(features, labels, mode, params):
  'pi_tensor': [BATCH_SIZE, go.N * go.N + 1]
  'value_tensor': [BATCH_SIZE]
  mode: a tf.estimator.ModeKeys (batchnorm params update for TRAIN only)
  - params: A dictionary
  + params: A dictionary (Typically derived from the FLAGS object.)
  Returns: tf.estimator.EstimatorSpec with props
  mode: same as mode arg
  predictions: dict of tensors
  