'By yannisxu (https://github.com/yannisxu)
å¢å è·åç¥ä¹ data-id çæ¹æ³æ¥ç¡®å®æ è¯çšæ·çå¯äžæ§ #24
(https://github.com/egrcc/zhihu-python/pull/24)'

def get_data_id(self):

    if (self.user_url == None):
        print "I'm    anonymous    user."
        return 0
    else:
        if (self.soup == None):
            self.parser()
        soup = self.soup
        data_id = soup.find('button', class_='zg-btn    zg-btn-follow    zm-rich-follow-btn')['data-id']
        return data_id
