import nibabel as nib
num=1
for i in range(155)
img = nib.load('F:/shujuji/train/'+str(num)+'/mask_GTV.nii.gz')
img_affine = img.affine
img = img.get_data()
img = img//255
nib.Nifti1Image(img,img_affine).to_filename('F:/shujuji/train/'+str(num)+'/mask_GTV.nii.gz')
num+=1