Download the pictures in your Pixiv bookmarks.

download_my_pixiv_bookmarks.py

# -*- coding: utf-8 -*-
import os
import time
from pixivpy3 import *
from multiprocessing import Pool

api = AppPixivAPI()
username = 'account'
password = 'password'
path = u'your path'
pixiv_id = 123456
os.chdir(path)
t = time.strftime('%Y-%m')
if not os.path.exists(t):
    os.mkdir(t)


def downloadImg(url):
    print(url)
    dp = os.path.join(path, t)
    api.download(url, path=dp)


def dirFiles(path):
    files = [i[2] for i in os.walk(path)]
    result = []
    for i in files:
        result.extend(i)
    return result


def main():
    api.login(username=username, password=password)

    files = dirFiles(path)
    favorite = api.user_bookmarks_illust(pixiv_id)
    fav_res = favorite['illusts']
    image_urls = []
    for i in fav_res:
        if i['meta_single_page'].has_key("original_image_url"):
            image_urls.append(i['meta_single_page']['original_image_url'])
        elif len(i['meta_pages']) != 0:
            image_urls.extend([u['image_urls']['original'] for u in i['meta_pages']])
    urls = filter(lambda x: os.path.basename(x) not in files, image_urls)
    print image_urls
    print urls
    p = Pool(10)
    p.map(downloadImg, urls)
    p.close()
    p.join()

if __name__ == '__main__':
    main()

Replace username password and path