Fix that the pretrained model doens't have use_att option.

Author: ruotianluo

dataloader.py

@@ -39,7 +39,7 @@ def __init__(self, opt):
         self.opt = opt
         self.batch_size = self.opt.batch_size
         self.seq_per_img = opt.seq_per_img
-        self.use_att = opt.use_att
+        self.use_att = getattr(opt, 'use_att', True)
 
         # load the json file which contains additional information about the dataset
         print('DataLoader loading json file: ', opt.input_json)