keypints don't work

[PythonImageDeveloper]

Hi ,
I want to only have some category but when i use arg.type=keypoints i got error :

Traceback (most recent call last):
File "anno_coco2voc.py", line 154, in
main(args)
File "anno_coco2voc.py", line 145, in main
parse_keypoints(content, args.output_dir)
File "anno_coco2voc.py", line 115, in parse_keypoints
keypoints = dict(zip(range(1, len(content['categories'][0]['keypoints'])+1), content['categories'][0]['keypoints']))
KeyError: 'keypoints'