Update meta_trainer.py

trainer/meta_trainer.py

@@ -352,7 +352,6 @@ class MetaTrainer(object):
                 vl=0
                 va=0
             else:
-                with torch.no_grad():
                 tqdm_gen = tqdm.tqdm(val_loader)
                 for i, batch in enumerate(tqdm_gen, 1):
                     if torch.cuda.is_available():