def fetch_access_token(self, code):
res = self._get(<EOL>'<STR_LIT>',<EOL>params={<EOL>'<STR_LIT>': self.app_id,<EOL>'<STR_LIT>': self.component.component_appid,<EOL>'<STR_LIT>': self.component.access_token,<EOL>'<STR_LIT:code>': code,<EOL>'<STR_LIT>': '<STR_LIT>',<EOL>}<EOL>)<EOL>self.access_token = res['<STR_LIT>']<EOL>self.open_id = res['<STR_LIT>']<EOL>self.refresh_token = res['<STR_LIT>']<EOL>self.expires_in = res['<STR_LIT>']<EOL>self.scope = res['<STR_LIT>']<EOL>return res<EOL>
获取 access_token

        :param code: 授权完成跳转回来后 URL 中的 code 参数
        :return: JSON 数据包