add gc for clearing gpu cache

predictor/cross_validation.py

 import pickle
 import torch
 import torch.nn as nn
+import gc
 
 from datetime import datetime
 
 def cv(args, out_dir):
     torch.cuda.set_per_process_memory_fraction(0.6, 0)
     # Clear any cached memory
+    gc.collect()
     torch.cuda.empty_cache()
     save_args(args, os.path.join(out_dir, 'args.json'))
     test_loss_file = os.path.join(out_dir, 'test_loss.pkl')
                 logging.info("Inner loop completed. Mean valid loss: {:.4f}".format(inner_loss))
                 logging.info("-" * n_delimiter)
                 losses.append(inner_loss)
+        gc.collect()
         torch.cuda.empty_cache()
         time.sleep(10)
         min_ls, min_idx = arg_min(losses)