@register.filter
def markdown_thumbnails(value):
    return text_filter('!\[(%(caption)s)?\][ ]?\((%(image)s)\)', value)
make cookie python 2 version use this method to get cookie list
dataset/ETHPy150Open python-thumbnails/python-thumbnails/thumbnails/templatetags/thumbnails.py/markdown_thumbnails--crossover with--dataset/ETHPy150Open binux/pyspider/pyspider/fetcher/cookie_utils.py/MockResponse.getheaders