Change confusing function name (#1669)

Author: lazylife7157

tensor2tensor/utils/beam_search.py

@@ -724,8 +724,9 @@ def inner_loop(i, alive_seq, alive_log_probs, finished_seq, finished_scores,
     return (i + 1, alive_seq, alive_log_probs, finished_seq, finished_scores,
             finished_flags, states)
 
-  def _is_finished(i, unused_alive_seq, alive_log_probs, unused_finished_seq,
-                   finished_scores, unused_finished_in_finished, unused_states):
+  def _is_not_finished(i, unused_alive_seq, alive_log_probs,
+                       unused_finished_seq, finished_scores,
+                       unused_finished_in_finished, unused_states):
     """Checking termination condition.
 
     We terminate when we decoded up to decode_length or the lowest scoring item
@@ -781,7 +782,7 @@ def _is_finished(i, unused_alive_seq, alive_log_probs, unused_finished_seq,
     state_struc = nest.map_structure(get_state_shape_invariants, states)
   (_, alive_seq, alive_log_probs, finished_seq, finished_scores,
    finished_flags, states) = tf.while_loop(
-       _is_finished,
+       _is_not_finished,
        inner_loop, [
            tf.constant(0), alive_seq, alive_log_probs, finished_seq,
            finished_scores, finished_flags, states