--max-size isnt recognized by prefetch?!

src/batch_processor.py

@@ -79,7 +79,8 @@ def process_file(accession, region):
         prefetch_start = datetime.now()
         # 'is larger than maximum allowed: skipped' solved by:
         # https://wiki.rc.hms.harvard.edu/display/O2/Aspera+to+download+NCBI+SRA+data
-        os.system('prefetch -X 35G '+accession)
+        #os.system('prefetch --max-size 35G '+accession)
+        os.system('prefetch '+accession)
         prefetch_time = datetime.now() - prefetch_start 
         sdb_log(sdb,accession,'prefetch_time',int(prefetch_time.seconds))
         os.system('mkdir -p tmp/')