Using sort_keys with python3's json.dumps Does Not Go Natural

If you create a function in the following form and produce the results, 1,11,99,100 will not be in natural order in the following form.

 1,100, 11,99

Is there any way, please let me know.

def score_summary(rows):

    return json.dumps({
        'time': by_time(rows),
        'userno': by_userno(rows)

    }, sort_keys = True, indent = 4)