bugfix, batch_bar doesn't exist if train started after all epochs com…

…pleted.

tqdm/keras.py

@@ -94,7 +94,7 @@ def on_epoch_begin(self, epoch, *_, **__):
                 raise KeyError('Unknown verbosity')
 
     def on_train_end(self, *_, **__):
-        if self.verbose:
+        if hasattr(self, 'batch_bar'):
             self.batch_bar.close()
         self.epoch_bar.close()