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import cString
import requests

from tornado.web import authenticated, RequestHandler

URL = 'https://api.weixin.qq.com/cgi-bin/wxaapp/createwxaqrcode'

def fetch_qrcode_image(path, width=430):
    params = {'access_token': 'access_token'}
    json_data = {
        'width': width,
        'path': path
    }
    res = requests.post(URL, params=params, json=json_data, timeout=3, verify=False)
    qrcode_image = cStringIO.StringIO(res.content)
    return qrcode_image.getvalue()

# tornado
class QRCodeHandler(RequestHandler):

    def get(self):
        path = self.get_argument('path')
        if not path:
            self.set_status(404)
            return
        qr_code = fetch_qrcode_image(path)
        if not qr_code:
            self.set_status(404)
            return
        self.set_header('Content-Type', 'image/jpeg')
        self.finish(qr_code)