Update train.py

 if torch.cuda.is_available: change to if torch.cuda.is_available(): because torch.cuda.is_available is a function, need '()', it is just a clerical error

Author: zhangchuangnankai

train.py

@@ -263,7 +263,7 @@ def save_network(network, epoch_label):
  save_filename = 'net_%s.pth'% epoch_label
  save_path = os.path.join('./model',name,save_filename)
  torch.save(network.cpu().state_dict(), save_path)
- if torch.cuda.is_available:
+ if torch.cuda.is_available():
  network.cuda(gpu_ids[0])