设置雪球 cookies，代码来自于
        https://github.com/shidenggui/easytrader/issues/269
        :param cookies: 雪球 cookies
        :type cookies: str

def _set_cookies(self, cookies):
        """设置雪球 cookies，代码来自于
        https://github.com/shidenggui/easytrader/issues/269
        :param cookies: 雪球 cookies
        :type cookies: str
        """
        cookie_dict = helpers.parse_cookies_str(cookies)
        self.s.cookies.update(cookie_dict)