TypeError: Caught TypeError in DataLoader worker process 0.

TypeError: Caught TypeError in DataLoader worker process 0.

Original Traceback (most recent call last):

File “/home/hpc/rzku/mlvl109h/.conda/envs/CineVN/lib/python3.10/site-packages/torch/utils/data/_utils/worker.py”, line 308, in _worker_loop

data = fetcher.fetch(index)

File “/home/hpc/rzku/mlvl109h/.conda/envs/CineVN/lib/python3.10/site-packages/torch/utils/data/_utils/fetch.py”, line 54, in fetch

return self.collate_fn(data)

File “/home/hpc/rzku/mlvl109h/.conda/envs/CineVN/lib/python3.10/site-packages/torch/utils/data/_utils/collate.py”, line 265, in default_co>

return collate(batch, collate_fn_map=default_collate_fn_map)

File “/home/hpc/rzku/mlvl109h/.conda/envs/CineVN/lib/python3.10/site-packages/torch/utils/data/_utils/collate.py”, line 132, in collate

return elem_type(*(collate(samples, collate_fn_map=collate_fn_map) for samples in zip(*batch)))

File “/home/hpc/rzku/mlvl109h/.conda/envs/CineVN/lib/python3.10/site-packages/torch/utils/data/_utils/collate.py”, line 132, in

return elem_type(*(collate(samples, collate_fn_map=collate_fn_map) for samples in zip(*batch)))

File “/home/hpc/rzku/mlvl109h/.conda/envs/CineVN/lib/python3.10/site-packages/torch/utils/data/_utils/collate.py”, line 150, in collate

raise TypeError(default_collate_err_msg_format.format(elem_type))

TypeError: default_collate: batch must contain tensors, numpy arrays, numbers, dicts or lists; found <class ‘NoneType’>

Based on the stacktrace it seems your Dataset.__getitem__ method returns None instead of valid tensors or arrays, so could you check why this might be the case?
Are you using a custom Dataset and forgot to return the samples?