Hi, congratulations on a great package, I really like Monai!
I was trying the tutorials and ran the 3D spleen segmentation. One of the features used in the Jupyter notebook was "Cache Dataset". It works fine with my dataset in the notebook, but then I re-wrote it into a script and it is throwing an error, as shown below. The issue is clearly with the Caching, since it works when I use just the "Dataset" module. Further, I noticed that you use the Dataset in your tutorial script as well and I was wondering if there is an underlying reason for that.
Your help would be very much appreciated
S.

`Traceback (most recent call last):a: [===== ]
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/transforms/utils.py", line 309, in apply_transform
return transform(data)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/transforms/io/dictionary.py", line 77, in call
data = self.loader(d[key], reader)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/transforms/io/array.py", line 103, in call
img = reader.read(filename)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/data/image_reader.py", line 145, in read
img.append(itk.imread(name, **kwargs_))
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/itkExtras.py", line 628, in imread
TemplateReaderType = itk.ImageFileReader
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/itkLazy.py", line 52, in getattribute
itkBase.LoadModule(module, namespace)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/itkBase.py", line 61, in LoadModule
swig.update(this_module.swig)
AttributeError: module 'itk.ITKIOImageBasePython' has no attribute 'swig'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "Unet_v1_train.py", line 229, in
main(data_dir, max_epochs=100, num_samples=10, num_val=4)
File "Unet_v1_train.py", line 118, in main
train_ds = CacheDataset(
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/data/dataset.py", line 278, in init
p.map(
File "/usr/lib/python3.8/multiprocessing/pool.py", line 364, in map
return self._map_async(func, iterable, mapstar, chunksize).get()
File "/usr/lib/python3.8/multiprocessing/pool.py", line 768, in get
raise self._value
File "/usr/lib/python3.8/multiprocessing/pool.py", line 125, in worker
result = (True, func(*args, **kwds))
File "/usr/lib/python3.8/multiprocessing/pool.py", line 48, in mapstar
return list(map(*args))
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/data/dataset.py", line 309, in _load_cache_item_thread
self._cache[i] = self._load_cache_item(item, transforms)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/data/dataset.py", line 297, in _load_cache_item
item = apply_transform(transform, item)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/transforms/utils.py", line 311, in apply_transform
raise type(e)(f"Applying transform {transform}.").with_traceback(e.traceback)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/transforms/utils.py", line 309, in apply_transform
return transform(data)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/transforms/io/dictionary.py", line 77, in call
data = self.loader(d[key], reader)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/transforms/io/array.py", line 103, in call
img = reader.read(filename)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/monai/data/image_reader.py", line 145, in read
img.append(itk.imread(name, **kwargs))
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/itkExtras.py", line 628, in imread
TemplateReaderType = itk.ImageFileReader
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/itkLazy.py", line 52, in getattribute
itkBase.LoadModule(module, namespace)
File "/home/ubuntu/envs/monai/lib/python3.8/site-packages/itkBase.py", line 61, in LoadModule
swig.update(this_module.swig)
AttributeError: Applying transform <monai.transforms.io.dictionary.LoadImaged object at 0x7f7703fa9d30>.`