captcher.py

import json, requests, urllib

url = 'https://2ch.hk/api/captcha/2chaptcha/id'
imageurl = 'https://2ch.hk/api/captcha/2chaptcha/image/'

count = 100
dirname = '/home/innermous/Downloads/'  # leave this field empty to download into current directory

for x in range(0, count):
    r = requests.get(url)
    json_data = json.loads(r.text)
    imagehash = json_data["id"]

    src = imageurl + imagehash
    filename = "{cat}captcha{num}.png".format(cat=dirname, num=x)

    urllib.request.urlretrieve(src, filename)

    print("Loaded {num} of {total}".format(num=x+1, total=count))