NameError: name 'img_bytes' is not defined

[wgfrhebnr]

Traceback (most recent call last):
File "dasr/train.py", line 11, in
train_pipeline(root_path)
File "/home/chenz/DASR/basicsr/train.py", line 155, in train_pipeline
train_data = prefetcher.next()
File "/home/chenz/DASR/basicsr/data/prefetch_dataloader.py", line 76, in next
return next(self.loader)
File "/home/chenz/anaconda3/envs/DASR4/lib/python3.7/site-packages/torch/utils/data/dataloader.py", line 628, in next
data = self._next_data()
File "/home/chenz/anaconda3/envs/DASR4/lib/python3.7/site-packages/torch/utils/data/dataloader.py", line 1333, in _next_data
return self._process_data(data)
File "/home/chenz/anaconda3/envs/DASR4/lib/python3.7/site-packages/torch/utils/data/dataloader.py", line 1359, in _process_data
data.reraise()
File "/home/chenz/anaconda3/envs/DASR4/lib/python3.7/site-packages/torch/_utils.py", line 543, in reraise
raise exception
NameError: Caught NameError in DataLoader worker process 0.
Original Traceback (most recent call last):
File "/home/chenz/anaconda3/envs/DASR4/lib/python3.7/site-packages/torch/utils/data/_utils/worker.py", line 302, in _worker_loop
data = fetcher.fetch(index)
File "/home/chenz/anaconda3/envs/DASR4/lib/python3.7/site-packages/torch/utils/data/_utils/fetch.py", line 58, in fetch
data = [self.dataset[idx] for idx in possibly_batched_index]
File "/home/chenz/anaconda3/envs/DASR4/lib/python3.7/site-packages/torch/utils/data/_utils/fetch.py", line 58, in
data = [self.dataset[idx] for idx in possibly_batched_index]
File "/home/chenz/DASR/dasr/data/DASR_dataset.py", line 114, in getitem
img_gt = imfrombytes(img_bytes, float32=True)
NameError: name 'img_bytes' is not defined

How to address this problem?