dataloaders for fastai

dataloader.py

import fastai.vision as faiv
import nibabel as nib

def open_nii(fn:str) -> faiv.Image:
    """ Return fastai `Image` object created from NIfTI image in file `fn`."""
    x = nib.load(str(fn)).get_data()
    return faiv.Image(torch.Tensor(x))
    
class NiftiItemList(faiv.ImageItemList):
    """ custom item list for nifti files """
    def open(self, fn:faiv.PathOrStr)->faiv.Image: return open_nii(fn)
    
class NiftiNiftiList(NiftiItemList):
    """ item list suitable for synthesis tasks """
    _label_cls = NiftiItemList