Fix a python exception issue on using Sequence object of keras with MirroredStrategy

tensorflow/python/keras/utils/data_utils.py

@@ -886,12 +886,15 @@ class OrderedEnqueuer(SequenceEnqueuer):
         `(inputs, targets)` or
         `(inputs, targets, sample_weights)`.
     """
-    try:
     while self.is_running():
-        inputs = self.queue.get(block=True).get()
+      try:
+        inputs = self.queue.get(block=True, timeout=5).get()
+        if self.is_running():
           self.queue.task_done()
         if inputs is not None:
           yield inputs
+      except queue.Empty:
+        pass
       except Exception:  # pylint: disable=broad-except
         self.stop()
         six.reraise(*sys.exc_info())