Update DICOM2NRRD.py

1. reading and storing ROIs/from DICOM header/DICOM2NRRD.py

@@ -190,7 +190,7 @@ def DCM2NRRD(input_path,output_path,getROI,exptype):
 
 
 #this is the parallel version generated by chatgpt
-from multiprocessing import Pool
+import multiprocessing
 def process_patient(ID_subj, input_path_subj,output_path,getROI,exptype):
     #number of files = number slices
     series_reader = sitk.ImageSeriesReader()