diff --git a/scripts/train.py b/scripts/train.py
index 61b60e02..1531646e 100644
--- a/scripts/train.py
+++ b/scripts/train.py
@@ -4,6 +4,7 @@
 import os
 import sys
 import time
+import copy
 
 from collections import defaultdict
 
@@ -324,9 +325,9 @@ def main(args):
 
                 # Save another checkpoint with model weights and
                 # optimizer state
-                checkpoint['g_state'] = generator.state_dict()
+                checkpoint['g_state'] = copy.deepcopy(generator.state_dict())
                 checkpoint['g_optim_state'] = optimizer_g.state_dict()
-                checkpoint['d_state'] = discriminator.state_dict()
+                checkpoint['d_state'] = copy.deepcopy(discriminator.state_dict())
                 checkpoint['d_optim_state'] = optimizer_d.state_dict()
                 checkpoint_path = os.path.join(
                     args.output_dir, '%s_with_model.pt' % args.checkpoint_name
@@ -460,9 +461,9 @@ def check_accuracy(
 ):
     d_losses = []
     metrics = {}
-    g_l2_losses_abs, g_l2_losses_rel = ([],) * 2
-    disp_error, disp_error_l, disp_error_nl = ([],) * 3
-    f_disp_error, f_disp_error_l, f_disp_error_nl = ([],) * 3
+    g_l2_losses_abs, g_l2_losses_rel = [], []
+    disp_error, disp_error_l, disp_error_nl = [], [], []
+    f_disp_error, f_disp_error_l, f_disp_error_nl = [], [], []
     total_traj, total_traj_l, total_traj_nl = 0, 0, 0
     loss_mask_sum = 0
     generator.eval()
@@ -578,3 +579,4 @@ def cal_fde(
 if __name__ == '__main__':
     args = parser.parse_args()
     main(args)
+