text: import argparse
  import csv
  
  from texmex_python import reader
  
  parser = argparse.ArgumentParser()
  parser.add_argument("filepath")
  parser.add_argument("save_basepath")
  parser.add_argument("split", type=int)
  args = parser.parse_args()
  
  for i, vec in enumerate(reader.read_bvec_iter(open(args.filepath))):
      if i % args.split == 0:
          fw = open("{}_split{}".format(args.save_basepath, i/args.split), "w+")
          writer = csv.writer(fw)
      writer.writerow(vec)
  