import tensorflow as tf


def benchmark_one_step(sess, fetches, step, batch_size,
                       step_train_times, trace_filename, summary_op=None):
  """Advance one step of benchmarking."""
  if trace_filename is not None and step == -1:
    run_options = tf.RunOptions(trace_level=tf.RunOptions.FULL_TRACE)
    run_metadata = tf.RunMetadata()
  else:
    run_options = None
    run_metadata = None
